Question

i am creating an application in which i want set different background images in main xml linearlayout.I have stored 5 image files on sd card .now i want to select a pic and set it as my maim xml linearlayout background.so it will replace the previous image and display the new image as background.

Answer 1

First assign an id to the main xml linearlayout, for example in the following case it is named” container”

    <!-- main.xml -->
<?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/container">
    <TextView  
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content" 
        android:text="@string/hello"
        />
</LinearLayout>

Then in the .java code you can find the layout object and set a drawable as its background:

package org.example.app;

import android.app.Activity;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;

public class Main extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        String pathName = "/sdcard/gif001.gif";
        Resources res = getResources();
        Bitmap bitmap = BitmapFactory.decodeFile(pathName);
        BitmapDrawable bd = new BitmapDrawable(res, bitmap);
        View view = findViewById(R.id.container);
        view.setBackgroundDrawable(bd);
    }
}

Regards

Ziteng Chen