Android 动态生成布局 （多层嵌套）

Android 除了能够载入xml文件，显示布局外，也能够代码生成布局，并通过setContentView(View view)方法显示布局。单独的一层布局，如一个主布局加一个控件（如ButtonimageView等）动态生成代码比較简单。以下仅仅给出演示样例代码：

package com.example.android_dongtaishengcheng;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.Toast;
import android.widget.RelativeLayout.LayoutParams;

public class MainActivity extends Activity
{
    RelativeLayout relativeLayout = null;
    private Button button;
    
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
	super.onCreate(savedInstanceState);
	relativeLayout = new RelativeLayout(this);
	LayoutParams params = new LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT,
		RelativeLayout.LayoutParams.MATCH_PARENT);
	relativeLayout.setLayoutParams(params);
	relativeLayout.setBackgroundResource(R.color.back);
	setContentView(relativeLayout);
	
	button = new Button(this);
	LayoutParams params2 = new LayoutParams(300, 300);
	button.setLayoutParams(params2);
	params2.addRule(RelativeLayout.CENTER_IN_PARENT);
	button.setText("hello");
	relativeLayout.addView(button);
	button.setOnClickListener(new View.OnClickListener()
	{
	    
	    @Override
	    public void onClick(View v)
	    {
		// TODO Auto-generated method stub
		startActivity(new Intent(MainActivity.this,SecondActivity.class));
	    }
	});
    }
}

以下进入重点：多层嵌套布局的动态生成。

情景描写叙述：父布局是一个线性布局，其子布局按竖直方向排列。子布局的子布局也是一个线性布局，按水平方向排列。

事实上非常easy，关键点在于。怎样控制主布局的子布局换行显示。即实现Orientation = "vertical"。能够在子布局外在加一层布局，即以下的drawParent()方法，该方法用来生成父布局的直接子布局，drawView()方法用来生成直接子布局的子布局（该布局也是多层嵌套）。能够实现例如以下图效果：

贴出代码例如以下：

/**
 * 
 */
package com.example.android_dongtaishengcheng;
import android.R.integer;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.LinearLayout.LayoutParams;

/**
 * @author zhiyuan
 * 
 * 2014-5-29 上午10:44:44
 * 
 */
public class SecondActivity extends Activity
{
    LinearLayout layout = null;
    LinearLayout line2 = null;
    LinearLayout line3 = null;
    LinearLayout line4 = null;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
	// TODO Auto-generated method stub
	super.onCreate(savedInstanceState);
	layout = new LinearLayout(this);
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
	layout.setLayoutParams(params);
	layout.setOrientation(LinearLayout.VERTICAL);
	setContentView(layout);

	// layout.addView(drawView(this));
	line2 = (LinearLayout) drawParent(this);
	line3 = (LinearLayout) drawParent(this);
	line4 = (LinearLayout) drawParent(this);
	for (int i = 0; i < 2; i++)
	{
	    line2.addView(drawView(SecondActivity.this, i));
	}
	for (int i = 0; i < 4; i++)
	{
	    line3.addView(drawView(SecondActivity.this, i));
	}
	for(int i = 0; i < 5; i++){
	    line4.addView(drawView(SecondActivity.this, i));
	}
	layout.addView(line2);
	layout.addView(line3);
	layout.addView(line4);
    }
    //生成子布局的子布局
    public View drawView(Context context, int count)
    {

	LinearLayout layout = new LinearLayout(context);
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,
		LayoutParams.WRAP_CONTENT, 1);
	params.gravity = Gravity.CENTER;
	layout.setOrientation(LinearLayout.HORIZONTAL);
	layout.setLayoutParams(params);
	if (count == 1)
	{
	    layout.setBackgroundResource(R.color.back);
	}
	RelativeLayout relativeLayout = new RelativeLayout(context);
	android.widget.RelativeLayout.LayoutParams params3 = new android.widget.RelativeLayout.LayoutParams(
		android.widget.RelativeLayout.LayoutParams.MATCH_PARENT,
		android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
	relativeLayout.setLayoutParams(params3);
	/*
	 * ImageView imageView = new ImageView(context); LayoutParams params2 = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
	 */
	Button imageView = new Button(context);
	android.widget.RelativeLayout.LayoutParams params2 = new android.widget.RelativeLayout.LayoutParams(android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT,
		android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
	//imageView.setGravity(RelativeLayout.CENTER_IN_PARENT);
	imageView.setText("測试");
	params2.addRule(RelativeLayout.CENTER_IN_PARENT);
	
	// imageView.setBackgroundResource(R.drawable.ic_launcher);
	imageView.setLayoutParams(params2);
        
	/*
	 * TextView textView = new TextView(context); LayoutParams params3 = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); textView.setText("測试专用");
	 * textView.setLayoutParams(params3);
	 */

	relativeLayout.addView(imageView);
	// layout.addView(textView);
        layout.addView(relativeLayout);
	return layout;
    }
    //生成主布局的子布局
    public View drawParent(Context context)
    {
	LinearLayout layout = new LinearLayout(context);
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
	// params.gravity = Gravity.CENTER_HORIZONTAL;
	layout.setOrientation(LinearLayout.HORIZONTAL);
	layout.setLayoutParams(params);
	return layout;
    }

}

附Demo下载地址：http://download.csdn.net/detail/laoziyueguo3/7423939