动态加控件

布局的layout文件内容：
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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:id="@+id/linearlayout">


<LinearLayout android:id="@+id/LinearLayout01"
android:layout_width="wrap_content" android:layout_height="wrap_content">
<Button android:layout_height="wrap_content" android:id="@+id/add"
  android:text="Add" android:layout_width="100px"></Button>
<Button android:layout_height="wrap_content"
  android:layout_width="100px" android:text="Remove" android:id="@+id/remove"></Button>
</LinearLayout>
<TextView android:id="@+id/TextView01" android:text="This is textView."
android:layout_width="fill_parent" android:gravity="center"
android:layout_height="50px"></TextView>

</LinearLayout>
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对应Activity的内容：
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package com.foxconn.dialog;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.LinearLayout;

public class DialogTest extends Activity implements OnClickListener {

    private Button add_btn, remove_btn;
    private LinearLayout linearLayout;
    private int index = 0;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        findViews();
        register();
    }

    private void register() {
        add_btn.setOnClickListener(this);
        remove_btn.setOnClickListener(this);
    }

    private void findViews() {
        add_btn = (Button) findViewById(R.id.add);
        remove_btn = (Button) findViewById(R.id.remove);
        linearLayout = (LinearLayout) findViewById(R.id.linearlayout);
    }

    protected View createView() {
        Button btn = new Button(this);
        btn.setId(index++);
        btn.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
        btn.setText("aaaaaa" + index);
        return btn;
    }

    private void removeView() {
        //获取linearlayout子view的个数
        int count = linearLayout.getChildCount();
        //研究整个LAYOUT布局，第0位的是含add和remove两个button的layout
        //第count-1个是那个文字被置中的textview
        //因此，在remove的时候，只能操作的是0<location<count-1这个范围的
        //在执行每次remove时，我们从count-2的位置即textview上面的那个控件开始删除~
        if (count - 2 > 0) {
            //count-2>0用来判断当前linearlayout子view数多于2个，即还有我们点add增加的button
            linearLayout.removeViewAt(count - 2);
        }
    }

    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.add:
            linearLayout.addView(createView(), 1);
            break;
        case R.id.remove:
            removeView();
            break;
        default:
            break;
        }
    }
}