Android练习之BitmapFactory.decodeFile加载SD卡文件

code

 

package com.example.flexd13;

import java.io.File;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

/**
 * 点击Button给ImageView赋值
 * 重点是从手机中找到图片，给Bitmap
 */
public class MainActivity extends Activity {
    
    private TextView tv1;
    private ImageView iv1;
    private Button bt1;
    private String fileName = "com.example.flexd13/baidu.gif";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        tv1 = (TextView)findViewById(R.id.tv1);
        iv1 = (ImageView)findViewById(R.id.iv1);
        bt1 = (Button)findViewById(R.id.bt1);
        
        bt1.setOnClickListener(listener);
        
    }
    
    /**
     * Listener
     */
    View.OnClickListener listener = new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            File file = new File(fileName);
            if(file.exists()){
                //从文件生成Bitmap
                Bitmap bitmap = BitmapFactory.decodeFile(fileName);
                iv1.setImageBitmap(bitmap);
                tv1.setText(fileName);
            }else{
                tv1.setText("ERROR file not found");
            }
        }
    };

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

}