Android在布局中动态添加view的两种方法

一、说明
添加视图文件的时候有两种方式:1、通过在xml文件定义layout；2、java代码编写

二、前言说明

1.构造xml文件

2.LayoutInflater

提到addview，首先要了解一下LayoutInflater类。这个类最主要的功能就是实现将xml表述的layout转化为View的功能。为了便于理解，我们可以将它与findViewById()作一比较，二者都是实例化某一对象，不同的是findViewById()是找xml布局文件下的具体widget控件实例化，而LayoutInflater找res/layout/下的xml布局文件来实例化的。

(1)创建

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

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

LayoutInflater inflater = getLayoutInflater();

这三种方法本质是相同的。

(2)inflate()

用LayoutInflater.inflate() 将LayOut文件转化成VIew。

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

3.添加视图文件

三、步骤
1、通过在xml文件定义layout(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 控件单击事件
        switch (v.getId()) {
        case R.id.sbtn_navback:
            this.finish();
            break;
        default:
            break;
        }
    }

}