java - 出现错误 : non-static method 'getResources()' cannot be referenced from a static context

Question

我正在使用Java在Android studio上开发一个rpg游戏，并且我在资源管理器的Drawable中有png图片。我正在尝试将可绘制对象转换为位图，但出现错误。

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;

public class Player implements GameObject{
    private int direction;
    private boolean move;

    public Player(int direction, boolean move){//constructior
        this.direction = direction;
        this.move = move;

        Drawable myDrawable = MainActivity.getResources().getDrawable(R.drawable.down_standing);
        Bitmap downStanding      = ((BitmapDrawable) myDrawable).getBitmap();
    }

    @Override
    public void draw(Canvas canvas){

    }

    @Override
    public void update(){

    }

    public void update(int direction, boolean move){
        this.direction = direction;
        this.move = move;
    }
}

对于MainActivity:

import androidx.appcompat.app.AppCompatActivity;

import android.app.Activity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.activity_main);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        Constants.SCREEN_WIDTH = dm.widthPixels;
        Constants.SCREEN_HEIGHT = dm.heightPixels;

        setContentView(new GamePanel(this));
    }
}

请帮忙。非常感谢!!

Answer 1

要调用getResources()，您需要一个Context引用，您不能静态调用它，所以这是错误的:

MainActivity.getResources()

要实现它，您应该提供一个 Context 参数，您可以从 Activity 获取该参数:

public Player(int direction, boolean move, Context context){  //constructior with Context
    this.direction = direction;
    this.move = move;

    Drawable myDrawable = context.getResources().getDrawable(R.drawable.down_standing);  // This is right
    Bitmap downStanding = ((BitmapDrawable) myDrawable).getBitmap();
}