Challenge missions
review the education system APP (two) as well as the education system APP (c)
Inspection login and registration module.
Please modify MainActivity and LoginActivity, after the welcome screen turned into the main interface, automatically jump into the login screen, the login is successful, return to the main screen, displays Hello World position at the main interface: user name + "sign in success."
Solution
Solve the task
to see what AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="cn.edu.gdmec.android.boxuegu">
<!--原为android:theme="@style/AppTheme"-->
<!--去除ActionBar标题栏-->
<!--添加应用图标，app_icon-->
<application
android:allowBackup="true"
android:icon="@drawable/app_icon"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.AppCompat.NoActionBar">
<activity android:name=".activity.SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<!--添加实现类-->
<activity android:name=".activity.MainActivity"></activity>
<activity android:name=".activity.LoginActivity"></activity>
<activity android:name=".activity.RegisterActivity"></activity>
</application>
</manifest>Then write code in MainActivity in, activity_main.xml add it to display, change the display helloWord account:
<?xml version="1.0" encoding="utf-8"?>
<!--任务：检验登录和注册模块-->
<!--在主界面的Hello World位置显示：用户名+“登录成功”-->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center">
<TextView
android:id="@+id/et_user_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="hello"
android:layout_gravity="center"/>
</LinearLayout>package cn.edu.gdmec.android.boxuegu.activity;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;
import cn.edu.gdmec.android.boxuegu.R;
/*任务在主界面的Hello World位置显示：用户名+“登录成功”*/
public class MainActivity extends AppCompatActivity {
private TextView et_user_name;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
et_user_name = findViewById(R.id.et_user_name);
Intent intent=new Intent(MainActivity.this,LoginActivity.class);
startActivityForResult(intent,1);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (data!=null){
String userName = data.getStringExtra("userName");
//if (!TextUtils.isEmpty(userName)){
Toast.makeText(MainActivity.this,"登陆成功："+userName, Toast.LENGTH_SHORT).show();
et_user_name.setText(userName);
//}
}
}
}Finally LoginActivity under:
data.putExtra("userName",userName);The education system APP (c) of the main interface
learning objectives: to master the development of registration and login module, the module enables switching function.
The main page, challenging task
Learning Objectives
The main interface has three modules, namely curriculum modules, exercises module, the user module. The user clicks on the bottom navigation bar to jump three modules can be achieved.
The main interface is used to make three switching modules. Fragment used as a carrier of the three interface modules.
Implementation tasks
placed image resources
image resources to use in this experiment are six, respectively
main_exercises_icon.png,
main_course_icon.png,
main_my_icon.png
main_exercises_icon_selected.png,
main_course_icon_selected.png,
main_my_icon_selected.png
to put to use the image resources drawrable into the folder.
activity_main layout
MainActivity page consists of two areas:
main_body put Fragment of
the bottom navigation bar main_bottom_bar
complete code of activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<LinearLayout
android:orientation="vertical"
android:background="@android:color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!--标题栏-->
<include layout="@layout/main_title_bar"/>
<!--放置Fragment的main_body-->
<RelativeLayout
android:id="@+id/main_body"
android:background="@android:color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
</RelativeLayout>
</LinearLayout>
<LinearLayout
android:id="@+id/main_bottom_bar"
android:layout_alignParentBottom="true"
android:background="#F2F2F2"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="55dp">
<RelativeLayout
android:layout_weight="1"
android:id="@+id/bottom_bar_course_btn"
android:layout_width="0dp"
android:layout_height="match_parent">
<TextView
android:id="@+id/bottom_bar_text_course"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="3dp"
android:gravity="center"
android:singleLine="true"
android:text="课 程"
android:textColor="#666666"
android:textSize="14sp"/>
<ImageView
android:layout_width="27dp"
android:layout_height="27dp"
android:layout_above="@+id/bottom_bar_text_course"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="3dp"
android:id="@+id/bottom_bar_image_course"
android:src="@drawable/main_course_icon"/>
</RelativeLayout>
<RelativeLayout
android:id="@+id/bottom_bar_exercises_btn"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="match_parent">
<TextView
android:id="@+id/bottom_bar_text_exercises"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="3dp"
android:gravity="center"
android:singleLine="true"
android:text="习 题"
android:textColor="#666666"
android:textSize="14sp"/>
<ImageView
android:layout_width="27dp"
android:layout_height="27dp"
android:layout_above="@+id/bottom_bar_text_exercises"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="3dp"
android:id="@+id/bottom_bar_image_exercises"
android:src="@drawable/main_exercises_icon"/>
</RelativeLayout>
<RelativeLayout
android:layout_weight="1"
android:id="@+id/bottom_bar_myinfo_btn"
android:layout_width="0dp"
android:layout_height="match_parent">
<TextView
android:id="@+id/bottom_bar_text_myinfo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="3dp"
android:gravity="center"
android:singleLine="true"
android:text="我"
android:textColor="#666666"
android:textSize="14sp"/>
<ImageView
android:layout_width="27dp"
android:layout_height="27dp"
android:layout_above="@+id/bottom_bar_text_myinfo"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="3dp"
android:id="@+id/bottom_bar_image_myinfo"
android:src="@drawable/main_my_icon"/>
</RelativeLayout>
</LinearLayout>
</RelativeLayout>Instantiate the control
tap MainActivity
public class MainActivity extends AppCompatActivity {
private RelativeLayout main_body;
private TextView bottom_bar_text_course;
private ImageView bottom_bar_image_course;
private RelativeLayout bottom_bar_course_btn;
private TextView bottom_bar_text_exercises;
private ImageView bottom_bar_image_exercises;
private RelativeLayout bottom_bar_exercises_btn;
private TextView bottom_bar_text_myinfo;
private ImageView bottom_bar_image_myinfo;
private RelativeLayout bottom_bar_myinfo_btn;
private LinearLayout main_bottom_bar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
private void initView() {
main_body = findViewById(R.id.main_body);
bottom_bar_text_course = findViewById(R.id.bottom_bar_text_course);
bottom_bar_image_course = findViewById(R.id.bottom_bar_image_course);
bottom_bar_course_btn = findViewById(R.id.bottom_bar_course_btn);
bottom_bar_text_exercises = findViewById(R.id.bottom_bar_text_exercises);
bottom_bar_image_exercises = findViewById(R.id.bottom_bar_image_exercises);
bottom_bar_exercises_btn = findViewById(R.id.bottom_bar_exercises_btn);
bottom_bar_text_myinfo = findViewById(R.id.bottom_bar_text_myinfo);
bottom_bar_image_myinfo = findViewById(R.id.bottom_bar_image_myinfo);
bottom_bar_myinfo_btn = findViewById(R.id.bottom_bar_myinfo_btn);
main_bottom_bar = findViewById(R.id.main_bottom_bar);
}
}Control instance of the part to complete it.
The method of switching a state of the bottom navigation bar
bottom navigation bar while clicking switch, there will be effects of discoloration.
MainActivity to add a setSelectStatus () method.
private void setSelectStatus(int index) {
switch (index){
case 0:
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon_selected);
bottom_bar_text_course.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_exercises.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon);
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon);
break;
case 1:
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon_selected);
bottom_bar_text_exercises.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_course.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon);
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon);
break;
case 2:
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon_selected);
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_course.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_exercises.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon);
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon);
break;
}
}In setSelectStatus () method in the index parameter to determine the currently selected button.
Response bottom of the navigation
method of the navigation bar color transitions written, followed by clicking response method.
Give MainActivity plus View.OnClickListener Interface
public class MainActivity extends AppCompatActivity implements View.OnClickListener{Alt + Enter generating onClick () method of
response in the navigation area generated onClick () method of adding.
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bottom_bar_course_btn:
setSelectStatus(0);
break;
case R.id.bottom_bar_exercises_btn:
setSelectStatus(1);
break;
case R.id.bottom_bar_myinfo_btn:
setSelectStatus(2);
break;
}
}Do not forget to add three RelativeLayout controls listener,
my habit is in initView () method Riga.
bottom_bar_course_btn.setOnClickListener(this);
bottom_bar_exercises_btn.setOnClickListener(this);
bottom_bar_myinfo_btn.setOnClickListener(this);At this point, the bottom navigation bar of the code is complete.
private void initView() {
main_body = findViewById(R.id.main_body);
bottom_bar_text_course = findViewById(R.id.bottom_bar_text_course);
bottom_bar_image_course = findViewById(R.id.bottom_bar_image_course);
bottom_bar_course_btn = findViewById(R.id.bottom_bar_course_btn);
bottom_bar_text_exercises = findViewById(R.id.bottom_bar_text_exercises);
bottom_bar_image_exercises = findViewById(R.id.bottom_bar_image_exercises);
bottom_bar_exercises_btn = findViewById(R.id.bottom_bar_exercises_btn);
bottom_bar_text_myinfo = findViewById(R.id.bottom_bar_text_myinfo);
bottom_bar_image_myinfo = findViewById(R.id.bottom_bar_image_myinfo);
bottom_bar_myinfo_btn = findViewById(R.id.bottom_bar_myinfo_btn);
main_bottom_bar = findViewById(R.id.main_bottom_bar);
bottom_bar_course_btn.setOnClickListener(this);
bottom_bar_exercises_btn.setOnClickListener(this);
bottom_bar_myinfo_btn.setOnClickListener(this);
}Create three fragment of
us still use methods Fragment of three modules interface to do it.
First, a new three layout file.
fragment_course.xml
fragment_exercises.xml
fragment_myinfo.xml
content layout files are similar to a big TextView, which read Fragment_1 / 2/3. Remember to change the background color and font color.
fragment_course.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Fragment_1"
android:textColor="@android:color/black"
android:textSize="50sp"/>
</LinearLayout>
fragment_exercises.xml<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Fragment_2"
android:textColor="@android:color/black"
android:textSize="50sp"/>
</LinearLayout>fragment_myinfo.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Fragment_3"
android:textColor="@android:color/black"
android:textSize="50sp"/>
</LinearLayout>Fragment build a package, the three Fragment into them
CourseFragment.java
package cn.edu.gdmec.android.boxuegu.fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import cn.edu.gdmec.android.boxuegu.R;
public class CourseFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_course, null);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}ExercisesFragment.java
package cn.edu.gdmec.android.boxuegu.fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import cn.edu.gdmec.android.boxuegu.R;
public class ExercisesFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_exercises, null);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}MyinfoFragment.java
package cn.edu.gdmec.android.boxuegu.fragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import cn.edu.gdmec.android.boxuegu.R;
public class MyinfoFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_myinfo, null);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}Three fragment display and switch
Fragment use the android.support.v4.app.Fragment
Next we put AppCompatActivity changed FragmentActivity in MainActivity years.
public class MainActivity extends FragmentActivity implements View.OnClickListener{Fragment added to the code in the following Activity
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.add(R.id.main_body,new CourseFragment()).commit();We wrote a setMain () method, used to open the initial page
private void setMain() {
this.getSupportFragmentManager().beginTransaction().add(R.id.main_body,new CourseFragment()).commit();
setSelectStatus(0);
}There is use of ligatures, with the above Fragment Activity code is added to the same effect, this depends on personal habits.
Call onCreate () method in
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setMain();
}When you click the bottom navigation bar to switch fragment response method Fragment switching we add in onClick () method in.
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bottom_bar_course_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new CourseFragment()).commit();
setSelectStatus(0);
break;
case R.id.bottom_bar_exercises_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new ExercisesFragment()).commit();
setSelectStatus(1);
break;
case R.id.bottom_bar_myinfo_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new MyinfoFragment()).commit();
setSelectStatus(2);
break;
}
}Complete MainActivity.java
package cn.edu.gdmec.android.boxuegu.activity;
import android.content.pm.ActivityInfo;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;
import cn.edu.gdmec.android.boxuegu.R;
import cn.edu.gdmec.android.boxuegu.fragment.CourseFragment;
import cn.edu.gdmec.android.boxuegu.fragment.ExercisesFragment;
import cn.edu.gdmec.android.boxuegu.fragment.MyinfoFragment;
/*任务在主界面的Hello World位置显示：用户名+“登录成功”*/
public class MainActivity extends FragmentActivity implements View.OnClickListener{
private RelativeLayout main_body;
private TextView bottom_bar_text_course;
private ImageView bottom_bar_image_course;
private RelativeLayout bottom_bar_course_btn;
private TextView bottom_bar_text_exercises;
private ImageView bottom_bar_image_exercises;
private RelativeLayout bottom_bar_exercises_btn;
private TextView bottom_bar_text_myinfo;
private ImageView bottom_bar_image_myinfo;
private RelativeLayout bottom_bar_myinfo_btn;
private LinearLayout main_bottom_bar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
//把Fragment加到Activity里的代码如下
/* FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.add(R.id.main_body,new CourseFragment()).commit();*/
setMain();
}
private void setMain() {
this.getSupportFragmentManager().beginTransaction().add(R.id.main_body,new MyinfoFragment()).commit();
setSelectStatus(2);
}
private void setSelectStatus(int index) {
switch (index){
case 0:
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon_selected);
bottom_bar_text_course.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_exercises.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon);
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon);
break;
case 1:
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon_selected);
bottom_bar_text_exercises.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_course.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon);
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon);
break;
case 2:
bottom_bar_image_myinfo.setImageResource(R.drawable.main_my_icon_selected);
bottom_bar_text_myinfo.setTextColor(Color.parseColor("#0097F7"));
bottom_bar_text_course.setTextColor(Color.parseColor("#666666"));
bottom_bar_text_exercises.setTextColor(Color.parseColor("#666666"));
bottom_bar_image_exercises.setImageResource(R.drawable.main_exercises_icon);
bottom_bar_image_course.setImageResource(R.drawable.main_course_icon);
break;
}
}
private void initView() {
main_body = findViewById(R.id.main_body);
bottom_bar_text_course = findViewById(R.id.bottom_bar_text_course);
bottom_bar_image_course = findViewById(R.id.bottom_bar_image_course);
bottom_bar_course_btn = findViewById(R.id.bottom_bar_course_btn);
bottom_bar_text_exercises = findViewById(R.id.bottom_bar_text_exercises);
bottom_bar_image_exercises = findViewById(R.id.bottom_bar_image_exercises);
bottom_bar_exercises_btn = findViewById(R.id.bottom_bar_exercises_btn);
bottom_bar_text_myinfo = findViewById(R.id.bottom_bar_text_myinfo);
bottom_bar_image_myinfo = findViewById(R.id.bottom_bar_image_myinfo);
bottom_bar_myinfo_btn = findViewById(R.id.bottom_bar_myinfo_btn);
main_bottom_bar = findViewById(R.id.main_bottom_bar);
bottom_bar_course_btn.setOnClickListener(this);
bottom_bar_exercises_btn.setOnClickListener(this);
bottom_bar_myinfo_btn.setOnClickListener(this);
}
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bottom_bar_course_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new CourseFragment()).commit();
setSelectStatus(0);
break;
case R.id.bottom_bar_exercises_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new ExercisesFragment()).commit();
setSelectStatus(1);
break;
case R.id.bottom_bar_myinfo_btn:
getSupportFragmentManager().beginTransaction().add(R.id.main_body,new MyinfoFragment()).commit();
setSelectStatus(2);
break;
}
}
}Well, is completed, there is no activity of the newly added category. The next challenge task!
Challenging task
for the first time to open the pages are Fragment_1, please modify the code so that the initial opening page is Fragment_3, do not forget to also change the color of the navigation bar at the bottom oh
Summarize
this is to take a good three-step Android!
❤️ Do not forget to leave your footprints learning [+ collection point Like Comments +]
Author Info:
[Author]: Jeskson
[original] Public number: Dada front-end bistro.
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