Android--动态添加控件

 

 

 

 

package com.mrzhu.edittest;import android.app.Activity;import android.os.Bundle;import android.view.ViewGroup;import android.widget.RelativeLayout;public class EditTestActivity extends Activity {/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);//自定义的带提示文本的EditText组件EditTextTest ed = new EditTextTest(this);//设置从左边140px处开始输入文本ed.setPadding(140, 0, 0, 0);//装载一个布局文件，向这个布局中动态添加一个EditTextRelativeLayout relativeLayout = (RelativeLayout) getLayoutInflater().inflate(R.layout.main, null);//创建一个LayoutParams对象RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);//设置android:layout_below属性的值 layoutParams.addRule(RelativeLayout.BELOW, R.id.button2);//动态添加EditTextrelativeLayout.addView(ed, layoutParams);//设置布局setContentView(relativeLayout);}}

自定义的EditText控件：

package com.mrzhu.edittest;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.util.AttributeSet;import android.widget.EditText;public class EditTextTest extends EditText {public EditTextTest(Context context) {super(context);}public EditTextTest(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);}public EditTextTest(Context context, AttributeSet attrs) {super(context, attrs);}@Overrideprotected void onDraw(Canvas canvas) {Paint paint = new Paint();paint.setTextSize(20);paint.setColor(Color.GRAY);canvas.drawText("输入提示文本:", 10, getHeight() / 2 + 5, paint);super.onDraw(canvas);}}

main.xml:

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/linearlayout"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="horizontal" >    <Button        android:id="@+id/button2"        android:layout_width="80dp"        android:layout_height="80dp"        android:layout_alignParentTop="true"        android:layout_centerHorizontal="true"        android:layout_marginTop="150dp"        android:onClick="click"        android:text="Button" /></RelativeLayout>