Android 自定义控件

1）本文简介

创建Android的自定义控件

通过前台、后台添加自定义控件

2）定义一个layout（activity_custom.xml）作为自定义控件的布局代码如下

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button" />

</LinearLayout>

3） 接下来写一个类(CustomUserControl.java)继承LinearLayout，导入刚刚的布局，并且设置需要的方法，从而使的能在代码中控制这个自定义控件内容的显示。

package com.example.androidapp;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

public class CustomUserControl extends LinearLayout{

private TextView textView1=null;
private Button button1=null;
public CustomUserControl(Context context){
super(context);
}
public CustomUserControl(Context context, AttributeSet attr){
super(context, attr);
LayoutInflater layoutInflater=
(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
layoutInflater.inflate(R.layout.activity_custom, this);
textView1=(TextView)findViewById(R.id.textView1);
button1=(Button)findViewById(R.id.button1);
}

/*设置显示文字*/
public void setTextViewText(String text){
textView1.setText(text);
}
}

4）前台(activity_main.xml)调用自定义控件代码如下

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<com.example.androidapp.CustomUserControl
android:id="@+id/customUserControl1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
</com.example.androidapp.CustomUserControl>

</LinearLayout>

5）后台(MainActivity.java)设置前台添加的用户控件和后台添加用户控件并设置代码如下

package com.example.androidapp;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.LinearLayout;

public class MainActivity extends Activity {

private CustomUserControl customUserControl1=null;
private CustomUserControl customUserControl2=null;
private LinearLayout linearLayout1=null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/*获取前台添加的自定义控件并操作*/
customUserControl1=(CustomUserControl)findViewById(R.id.customUserControl1);
customUserControl1.setTextViewText("前台添加自定义控件");
/*后台添加自定义控件并操作*/
linearLayout1=(LinearLayout)findViewById(R.id.linearLayout1);
customUserControl2=new CustomUserControl(MainActivity.this, null);
customUserControl2.setTextViewText("后台添加自定义控件");
linearLayout1.addView(customUserControl2);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

}