android圖像「查看器」應用程序

Question

我想創建一個android應用程序，該應用程序可以讓我顯示全屏圖像，並在上面顯示下一個和上一個按鈕以在它們之間進行更改。

任何人都可以指向我的一些教程，我可以找到類似的東西說明嗎？

如果沒有，最好的方法來使用圖像到應用程序？我已經嘗試了幾種創建圖像的對象類的方法，並用drawable在每個使用Bitmap Factory返回圖像的情況下實例化它，但這不起作用。

我是一名初學者，可以真正使用參考資料，但無法找到涵蓋此主題的任何有用內容。

Answer 1

作爲一個新手我自己一直在與此工作，這很簡單。下面是一些代碼（也許有更好的方法，但是這是我想出如何做到這一點）：

package com.imageviewexample; 

import android.app.Activity;  
import android.os.Bundle; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.ImageView; 

public class ImageViewExample extends Activity implements OnClickListener { 

    /** Called when the activity is first created. */ 

    int image_index = 0; 
    private static final int MAX_IMAGE_COUNT = 3; 

    private int[] mImageIds = { 
      R.raw.image1, 
      R.raw.image2, 
      R.raw.image3 
    }; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     Button btnPrevious = (Button)findViewById(R.id.previous_btn); 
     btnPrevious.setOnClickListener(this);  
     Button btnNext = (Button)findViewById(R.id.next_btn); 
     btnNext.setOnClickListener(this); 

     showImage();   

    } 

    private void showImage() { 

     ImageView imgView = (ImageView) findViewById(R.id.myimage);    
     imgView.setImageResource(mImageIds[image_index]);  

    } 

    public void onClick(View v) { 

     switch (v.getId()) { 

      case (R.id.previous_btn): 

       image_index--; 

       if (image_index == -1) {      
        image_index = MAX_IMAGE_COUNT - 1;     
       } 

       showImage(); 

      break; 

      case (R.id.next_btn): 

       image_index++; 

       if (image_index == MAX_IMAGE_COUNT) {    
       image_index = 0;     
      } 

       showImage(); 

      break;  

     } 

    } 
} 

這是main.xml：

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    > 

<Button 
    android:id="@+id/previous_btn" 
    android:layout_width="124dip" 
    android:layout_height="wrap_content" 
    android:text="Previous" 
    /> 

<Button 
    android:id="@+id/next_btn" 
    android:layout_width="124dip" 
    android:layout_height="wrap_content" 
    android:layout_toRightOf="@+id/previous_btn" 
    android:text="Next" 
    /> 

<ImageView 
    android:id="@+id/myimage" 
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:layout_below="@+id/previous_btn" 
    />   

</RelativeLayout> 

Answer 2

這是一個圖片瀏覽器解決方案與網格視圖的圖片資源，您可以選擇一個圖片，並顯示爲一個單一的圖片。在這個單一的圖片視圖，這是用PictureViewer.java完成，你可以瀏覽投擲資源圖片使用左鍵和右鍵。您也可以返回到使用HelloGridViewActivity.java完成的網格視圖。 ImageAdapter.java用於定義網格視圖資源和方法。希望這有助於：

HelloGridViewActivity.java：

package com.example.hellogridview; 

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemClickListener; 
import android.widget.GridView; 

public class HelloGridViewActivity extends Activity { 

private long prev=0,next= 0; 

@Override 
public void onCreate(Bundle savedInstanceState) { 



    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    final GridView gridview = (GridView) findViewById(R.id.gridview); 
    gridview.setAdapter(new ImageAdapter(this)); 

    gridview.setOnItemClickListener(new OnItemClickListener() { 
    public void onItemClick(AdapterView<?> parent, View v, int position, long id) { 


      prev = ImageAdapter.getPrevItemId(position); 
      next = ImageAdapter.getNextItemId(position); 

      showImage(gridview.getAdapter().getItemId(position),position); 


     } 
    }); 

} 
private void showImage(long id, int pos){ 
    Intent pictureViewer = new Intent(this, PictureViewer.class); 
    pictureViewer.putExtra("pictureId",id); 
    pictureViewer.putExtra("picturePosition", pos); 
    pictureViewer.putExtra("picturePrevId", prev); 
    pictureViewer.putExtra("pictureNextId", next); 

    startActivityForResult(pictureViewer,0); 

    } 
}  

ImageAdapter.java：

package com.example.hellogridview; 

import android.content.Context; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.BaseAdapter; 
import android.widget.GridView; 
import android.widget.ImageView; 

public class ImageAdapter extends BaseAdapter { 
private Context mContext; 

public ImageAdapter(Context c) { 
    mContext = c; 
} 

public int getCount() { 
    return mThumbIds.length; 
} 

public Object getItem(int position) { 
    return null; 
} 

public long getItemId(int position) { 
    return mThumbIds[position]; 
} 

public static long getPrevItemId(int position) { 
    if(--position<0) position = 21; 
    return mThumbIds[position]; 
} 

public static long getNextItemId(int position) { 
    if(++position>21) position = 0; 
    return mThumbIds[position]; 
} 

// create a new ImageView for each item referenced by the Adapter 
public View getView(int position, View convertView, ViewGroup parent) { 
    ImageView imageView; 
    if (convertView == null) { // if it's not recycled, initialize some attributes 
     imageView = new ImageView(mContext); 
     imageView.setLayoutParams(new GridView.LayoutParams(85, 85)); 
     imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); 
     imageView.setPadding(8, 8, 8, 8); 
    } else { 
     imageView = (ImageView) convertView; 
    } 

    imageView.setImageResource(mThumbIds[position]); 
    return imageView; 
} 

// references to our images 
private static Integer[] mThumbIds = { 
     R.drawable.sample_2, R.drawable.sample_3, 
     R.drawable.sample_4, R.drawable.sample_5, 
     R.drawable.sample_6, R.drawable.sample_7, 
     R.drawable.sample_0, R.drawable.sample_1, 
     R.drawable.sample_2, R.drawable.sample_3, 
     R.drawable.sample_4, R.drawable.sample_5, 
     R.drawable.sample_6, R.drawable.sample_7, 
     R.drawable.sample_0, R.drawable.sample_1, 
     R.drawable.sample_2, R.drawable.sample_3, 
     R.drawable.sample_4, R.drawable.sample_5, 
     R.drawable.sample_6, R.drawable.sample_7 
    }; 
}  

PictureViewer.java：

package com.example.hellogridview; 

import android.app.Activity; 
import android.content.Intent; 
import android.graphics.drawable.Drawable; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.widget.Button; 
import android.widget.ImageView; 


public class PictureViewer extends Activity { 

long picItem,picPrevItem,picNextItem; 
int picPosition; 
private ImageView m_vwImage; 


public void onCreate(Bundle savedInstanceState){ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.picture_layout); 


    //citanje podataka prosledjenih ovoj aktivnosti 
    //namera koja je pokrenula ovu aktivnost 
    Intent i = getIntent(); 

    picItem = i.getLongExtra("pictureId", -1); 
    picPrevItem = i.getLongExtra("picturePrevId", -1); 
    picNextItem = i.getLongExtra("pictureNextId", -1); 
    picPosition = i.getIntExtra("picturePosition", -1); 
    m_vwImage = (ImageView) findViewById(R.id.imageview); 


    //menjamo ulazne vrednosti da bi ih takve prosledili kao povratne 
    Log.i("Nemanja", "picItem" + picItem); 

    Drawable image = getResources().getDrawable((int)picItem); 
    m_vwImage.setImageDrawable(image); 


    Button startButton = (Button) findViewById(R.id.return_button); 
    startButton.setOnClickListener(new View.OnClickListener(){ 
     public void onClick(View view){ 
      finish(); 
     } 
    });  

    Button leftButton = (Button) findViewById(R.id.left_button); 
    leftButton.setOnClickListener(new View.OnClickListener(){ 
     public void onClick(View view){ 
      Drawable imagePrev = getResources().getDrawable((int)picPrevItem); 
      m_vwImage.setImageDrawable(imagePrev); 

      if(--picPosition<0) picPosition = 21; 
      picPrevItem = (ImageAdapter.getPrevItemId(picPosition)); 
      picNextItem = (ImageAdapter.getNextItemId(picPosition)); 

     } 
    }); 

    Button rightButton = (Button) findViewById(R.id.right_button); 
    rightButton.setOnClickListener(new View.OnClickListener(){ 
     public void onClick(View view){ 
      Drawable imageNext = getResources().getDrawable((int)picNextItem);  
      m_vwImage.setImageDrawable(imageNext); 

      if(++picPosition>21) picPosition = 0; 
      picNextItem = (ImageAdapter.getNextItemId(picPosition)); 
      picPrevItem = (ImageAdapter.getPrevItemId(picPosition)); 
     } 
    }); 
} 

}

HelloGridView清單：

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="com.example.hellogridview" 
android:versionCode="1" 
android:versionName="1.0" > 

<uses-sdk android:minSdkVersion="8" /> 

<application 
    android:icon="@drawable/ic_launcher" 
    android:label="@string/app_name" > 
    <activity 
     android:name=".HelloGridViewActivity" 
     android:label="@string/app_name" > 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
    <activity 
     android:name=".PictureViewer" 
     android:label="@string/app_name" > 
     <intent-filter> 
      <action android:name="android.intent.action.VIEW" /> 

      <category android:name="android.intent.category.DEFAULT" /> 
     </intent-filter> 
    </activity> 
</application> 

</manifest>