android -> two ways to dynamically add view in layout

 

 

Reprinted from: http://blog.csdn.net/Xd_Yu/article/details/51455609

 

1. 
There are two ways to add a view file: 1. By defining the layout in the xml file; 2. Writing in Java code

2. Introduction

1. Construct the xml file

2.LayoutInflater

When it comes to addview, we must first understand the LayoutInflater class. The main function of this class is to realize the function of converting the layout expressed by xml into View. In order to facilitate understanding, we can compare it with findViewById(), both of which are instantiating an object, the difference is that findViewById() is to find the specific widget control instantiation under the xml layout file, and LayoutInflater finds res/ The xml layout file under layout/ is instantiated.

(1) Create

LayoutInflater inflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);或

LayoutInflater inflater = LayoutInflater.from(Activity.this);或

LayoutInflater inflater = getLayoutInflater();

These three methods are essentially the same.

(2)inflate()

Use LayoutInflater.inflate() to convert LayOut files to VIew.

View view = inflater.inflate(R.layout.block_gym_album_list_item, null);

3. Add a view file

3. Step 
1. By defining the layout in the xml file (block_gym_album_list_item.xml)

<linearlayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:padding="5dp">

        <imageview
          android:id="@+id/iv_head_album"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:src="@drawable/defaulthead">
        </imageview>
</linearlayout>

 

activity_dynamic

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/ll_parent"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <include
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            layout="@layout/block_head_back">
        </include>
</linearlayout>

 

3、MainActivity

package com.gxtag.gym.ui;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;

import com.gxtag.gym.R;
import com.icq.app.widget.StatedButton;

public class MainActivityextends Activity implements OnClickListener{

    private Context mContext;
    private TextView mTv_title;
    private String title = "动态添加布局";
    private StatedButton mSbtn_back;
    private LinearLayout mLl_parent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_dynamic);
        mContext=this;
        initView();
        mLl_parent.addView(addView1());
        mLl_parent.addView(addView2());
    }

    private void initView() {
        // TODO 初始化视图
        mLl_parent=(LinearLayout) findViewById(R.id.ll_parent);
        mTv_title = (TextView) findViewById(R.id.tv_title);
        mTv_title.setText(String.format(String.format(
                getResources().getString(R.string.title), title)));
        mSbtn_back = (StatedButton) findViewById(R.id.sbtn_navback);
        mSbtn_back.setOnClickListener(this);  
    }

    private View addView1() {
        // TODO 动态添加布局(xml方式)
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams( 
                        LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);       //LayoutInflater inflater1=(LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//      LayoutInflater inflater2 = getLayoutInflater();
        LayoutInflater inflater3 = LayoutInflater.from(mContext);
        View view = inflater3.inflate(R.layout.block_gym_album_list_item, null);
        view.setLayoutParams(lp);
        return view;
        }

    private View addView2() {
        // TODO 动态添加布局(java方式)
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams( 
                    LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT); 
        LinearLayout view = new LinearLayout(this); 
        view.setLayoutParams(lp);//设置布局参数 
        view.setOrientation(LinearLayout.HORIZONTAL);// 设置子View的Linearlayout// 为垂直方向布局 
        //定义子View中两个元素的布局 
        ViewGroup.LayoutParams vlp = new ViewGroup.LayoutParams( 
                ViewGroup.LayoutParams.WRAP_CONTENT, 
                ViewGroup.LayoutParams.WRAP_CONTENT); 
        ViewGroup.LayoutParams vlp2 = new ViewGroup.LayoutParams( 
                ViewGroup.LayoutParams.WRAP_CONTENT, 
                ViewGroup.LayoutParams.WRAP_CONTENT); 

        TextView tv1 = new TextView(this); 
        TextView tv2 = new TextView(this); 
        tv1.setLayoutParams(vlp);//设置TextView的布局 
        tv2.setLayoutParams(vlp2); 
        tv1.setText("姓名:"); 
        tv2.setText("李四"); 
        tv2.setPadding(calculateDpToPx(50), 0, 0, 0);//设置边距 
        view.addView(tv1);//将TextView 添加到子View 中 
        view.addView(tv2);//将TextView 添加到子View 中 
        return view; 
    }

    private int calculateDpToPx(int padding_in_dp){
        final float scale = getResources().getDisplayMetrics().density;
        return  (int) (padding_in_dp * scale + 0.5f);
    }


    @Override
    public void onClick(View v) {
        // TODO control click event
        switch (v.getId()) {
        case R.id.sbtn_navback:
            this.finish();
            break;
        default:
            break;
        }
    }

}