在android应用开发时，可能会用到夜间模式，一般的解决方案就是用主题。夜间模式一般就涉及道背景，亮度，字体颜色等，所以可以简单通过自定义组件实现。接下来就介绍一种解决方案：只需要简单的依赖自定义库，初始化，并使用库里面自定义组件即可。Demo和组件库下载地址：http://download.csdn.net/detail/itjianghuxiaoxiong/8724459 ；
作夜间模式无非就两种状态：一种是夜间，一种是日间。然后就是监听状态的改变，通知布局切换状态。
1.监听状态改变，并发通知：采用观察者模式，当观察者发生改变时通知被观察者刷新组件；
2.自定义布局：自定已常用组件，并添加两种模式属性，方便定义不同模式样式。
初始化类：
package com.ml.dayornight.theme.view;
import android.content.Context;
import android.content.SharedPreferences;
import java.util.Observable;
/**
* @Package com.ml.dayornight.theme.view
* @ClassName: ThemeInit
* @Description: 初始化夜间模式
* @author malong
* @date May 20, 2015 6:32:57 PM
*/
public class ThemeInit {
public static ViewObservable mViewObservable;
public static SharedPreferences sharedPreferences;
public static final String THEME_MODE = "isDay";
public ThemeInit(Context context) {
mViewObservable = new ViewObservable();
sharedPreferences = context.getSharedPreferences("day_or_night", Context.MODE_PRIVATE);
}
/**
* @Package com.ml.dayornight.theme.view
* @ClassName: ViewObservable
* @Description: 创建一个被观察者
* @author malong
* @date May 20, 2015 3:41:14 PM
*/
public class ViewObservable extends Observable {
public void observableChange() {
setChanged();
notifyObservers();
}
}
/**
* @Description: 保存夜间模式状态
* @param key
* @param value
* @return void
* @author malong
* @date May 20, 20153:37:51 PM
*/
public static void saveBoolean(String key, Boolean value) {
sharedPreferences.edit().putBoolean(key, value).commit();
}
/**
* @Description: 读取夜间模式状态
* @param key
* @param defValue
* @return
* @return Boolean
* @author malong
* @date May 20, 20153:40:39 PM
*/
public static Boolean getBoolean(String key, Boolean defValue) {
return sharedPreferences.getBoolean(key, defValue);
}
public static Boolean isDay() {
return sharedPreferences.getBoolean(THEME_MODE, true);
}
}
自定义组件类EditText：
package com.ml.dayornight.theme.view;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.EditText;
import java.util.Observable;
import java.util.Observer;
/**
* @Package com.ml.dayornight.theme.view
* @ClassName: ThemeRelativeLayout
* @Description: 可设置夜间模式EditText
* @author malong
* @date May 18, 2015 6:24:13 PM
*/
public class ThemeEditText extends EditText {
private Drawable nightBackground, dayBackground;// 设置日间和夜间的背景（可以是颜色值，图片，或selector）
private float dayAlpha, nightAlpha;// 设置日间和夜间的透明度
private ColorStateList dayTextColor, nightTextColor, dayHintTextColor, nightHintTextColor;
/**
* @Description: 构造函数,初始化日间夜间模式
* @param @param context
* @author malong
* @date May 18, 20156:25:12 PM
*/
public ThemeEditText(Context context) {
super(context);
init(context, null, 0);
}
/**
* @Description: 构造函数,初始化日间夜间模式
* @param @param context
* @param @param attrs
* @author malong
* @date May 18, 20156:25:12 PM
*/
public ThemeEditText(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs, 0);
}
/**
* @Description: 构造函数,初始化日间夜间模式
* @param @param context
* @param @param attrs
* @param @param defStyle
* @author malong
* @date May 18, 20159:18:13 PM
*/
public ThemeEditText(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs, defStyle);
}
/**
* @Description: 初始化日间夜间模式
* @return void
* @author malong
* @date May 18, 20156:25:12 PM
*/
private void init(Context context, AttributeSet attrs, int defStyle) {
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.day_or_night);
/**
* 此处参TextView源码
*/
if (a != null) {
dayAlpha = a.getFloat(R.styleable.day_or_night_dayAlpha, 1.0f);
nightAlpha = a.getFloat(R.styleable.day_or_night_nightAlpha, 1.0f);
dayBackground = a.getDrawable(R.styleable.day_or_night_dayBackground);
nightBackground = a.getDrawable(R.styleable.day_or_night_nightBackground);
int n = a.getIndexCount();
for (int i = 0; i < n; i++) {
int attr = a.getIndex(i);
switch (attr) {
case R.styleable.day_or_night_dayTextColor:
dayTextColor = a.getColorStateList(attr);
break;
case R.styleable.day_or_night_nightTextColor:
nightTextColor = a.getColorStateList(attr);
break;
case R.styleable.day_or_night_dayHintTextColor:
dayHintTextColor = a.getColorStateList(attr);
break;
case R.styleable.day_or_night_nightHintTextColor:
nightHintTextColor = a.getColorStateList(attr);
break;
}
}
a.recycle();
}
if (ThemeInit.mViewObservable != null) {
ThemeInit.mViewObservable.addObserver(new ViewObserver());
}
changeBackground();
}
/**
* @Description: 改变控件的背景色
* @param context2
* @return void
* @author malong
* @date May 18, 20156:25:12 PM
*/
public void changeBackground() {
if (ThemeInit.sharedPreferences != null) {
if (ThemeInit.isDay()) {// 日间
if (dayBackground != null) {
this.setBackground(dayBackground);
}
if (dayAlpha != 1.0f) {
this.setAlpha(dayAlpha);
}
if (dayTextColor != null) {
this.setTextColor(dayTextColor);
}
if (dayHintTextColor != null) {
this.setHintTextColor(dayHintTextColor);
}
} else {// 夜间
if (nightBackground != null) {
this.setBackground(nightBackground);
}
if (nightAlpha != 1.0f) {
this.setAlpha(nightAlpha);
}
if (nightTextColor != null) {
this.setTextColor(nightTextColor);
}
if (nightHintTextColor != null) {
this.setHintTextColor(nightHintTextColor);
}
}
}
}
/**
* @Package com.ccdt.news.ui.view
* @ClassName: ViewObserver
* @Description: 观察者
* @author malong
* @date May 18, 20156:25:12 PM
*/
public class ViewObserver implements Observer {// 观察者
@Override
public void update(Observable observable, Object data) {
changeBackground();
}
}
}
自定义属性文件：
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="day_or_night">
<attr name="dayAlpha" format="float" />
<attr name="nightAlpha" format="float" />
<attr name="dayTextColor" format="color" />
<attr name="nightTextColor" format="color" />
<attr name="dayHintTextColor" format="color" />
<attr name="nightHintTextColor" format="color" />
<attr name="dayBackground" format="reference|color" />
<attr name="nightBackground" format="reference|color" />
</declare-styleable>
</resources>在xml布局中使用：
<com.ml.dayornight.theme.view.ThemeEditText
android:id="@+id/edit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/title"
android:layout_margin="10dp"
android:hint="@string/text_hint"
android:imeOptions="actionSearch"
android:maxLines="2"
app:dayBackground="@drawable/theme_edit_text_background_of_day"
app:dayHintTextColor="#34d243"
app:dayTextColor="@android:color/black"
app:nightBackground="@drawable/theme_edit_text_background_of_night"
app:nightHintTextColor="#55DDDDDD"
app:nightTextColor="#DD00DD" />在activity中调用：
package com.ml.dayornightdome;
import android.app.Activity;
import android.os.Bundle;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import com.ml.dayornight.theme.view.ThemeInit;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
new ThemeInit(getApplicationContext());// 初始化夜间模式,可在Application中初始化，只需初始化一次。
setContentView(R.layout.activity_main);
CheckBox mCheckBox = (CheckBox) findViewById(R.id.setting_night_check_box);
mCheckBox.setChecked(!ThemeInit.isDay());
mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
ThemeInit.saveBoolean(ThemeInit.THEME_MODE, !isChecked);
if (ThemeInit.mViewObservable != null) {
ThemeInit.mViewObservable.observableChange();
}
}
});
}
}
当然，我们不用自定义所有view，而是选在改变父view的颜色，子view一般可以透明不设置颜色。库里面的view基本够用了，有特殊需求可以按照此方法自定义。