Android 动态生成布局 （多层嵌套）

时间：2021-05-24 14:56:37

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Button\imageView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：

Android 动态生成布局 （多层嵌套）

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

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