Android：使用位图使用android studio显示图像时出错

Posted 2023-04-19

【中文标题】Android：使用位图使用android studio显示图像时出错

【英文标题】：Android: Error while using bitmap to display image using android studio

【发布时间】：2015-08-31 23:26:16

【问题描述】：

我创建了一个 10x10 的网格，现在想将玩家的图像放置在其中一个网格方块内。为此，我认为我必须使用位图？我将把我所有的代码放在下面。为了尝试这样做，我创建了一个游戏类，它设置并获取玩家图像的 x 位置。然后我创建了一个播放器类，我尝试在其中添加图像，使用 Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.sokobanplayer1); 我在 getResources 下不断收到错误，所以我在游戏中创建了一个获取资源方法，但它没有解决问题。有人可以告诉我如何做到这一点，我的代码如下。

//DRAW CLASS
public class Draw extends View 
Paint red = new Paint();
Paint green = new Paint();

int rectSide = 1000;

public Draw(Context context) 
    super(context);
    red.setColor(Color.RED);
    green.setColor(Color.GREEN);
    red.setStrokeWidth(8);
    green.setStrokeWidth(8);


public void drawGrid(Canvas canvas) 

    int width = canvas.getWidth();
    int height = canvas.getHeight();


    float startX = (width / 2) - (rectSide / 2);
    float stopX = (width / 2) + (rectSide / 2);
    float startY = (height / 2) - (rectSide / 2);
    float stopY = (height / 2) + (rectSide / 2);

    for (int i = 0; i < 1100; i += 100) 
        float newY = startY + i;
        canvas.drawLine(startX, newY, stopX, newY, green);
    

    for (int i = 0; i < 1100; i += 100) 

        float newX = startX + i;
        canvas.drawLine(newX, startY, newX, stopY, green);
    


@Override
public void onDraw(Canvas canvas) 

    drawGrid(canvas);



//GAME CLASS
public class Game 

Bitmap image;
int x;
int y;
int height;
int width;


public void setX(int x)
    this.x = x;


public void setY(int y)
    this.y = y;


public int getX()
    return x;


public int getY()
    return y;


public int getHeight()
    return height;


public int getWidth()
    return width;


public Bitmap getResources()
    return image;





//PLAYER CLASS
public class Player extends Game 

public Player(Bitmap res, int w, int h)

    image = res;
    x = 300;
    y = 300;
    height = h;
    width = w;

    Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.sokobanplayer1);




//MAIN ACTIVITY
public class MainActivity extends Activity 
Draw draw;

@Override
protected void onCreate(Bundle savedInstanceState) 
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.activity_main);

    draw = new Draw(this);
    draw.setBackgroundColor(Color.BLUE);
    setContentView(draw);



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


@Override
public boolean onOptionsItemSelected(MenuItem item) 
    int id = item.getItemId();

    if (id == R.id.action_settings) 
        return true;
    
    return super.onOptionsItemSelected(item);

【问题讨论】：

传递 context.getResources()

将上下文传递给 Player 类的构造函数

消除了错误但图像不显示在网格上？这是为什么？

【参考方案1】：

用这个替换你的 Player 类：

//PLAYER CLASS
class Player extends Game 

    public Player(Context context, int w, int h)

        x = 300;
        y = 300;
        height = h;
        width = w;

        image = BitmapFactory.decodeResource(context.getResources(), R.drawable.sokobanplayer1);