java - 如何根据屏幕尺寸启动 Activity ？

Question

因此，我检查我的 main_activity 类，如果我的屏幕尺寸是 mdpi 或 hdpi，并根据情况我需要在游戏 Activity 中启动适当的方法。我的数据库中有两个表，其中包含 mdpi 和 hdpi 图像。但我什么也没得到。只有我的空白主要 Activity 。有什么问题？这是我的主要 Activity :

public class MainActivity extends Activity {

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

            Display display = getWindowManager().getDefaultDisplay(); 
            int width = display.getWidth();
            int height = display.getHeight();

            if((width>320) && (width<480)){
                Intent i = new Intent(MainActivity.this, GameDanska.class);
                i.putExtra("myMethod", "nextQuestionMDPI");
                startActivity(i);

            }
            else if((width>480) && (width<720)){
                Intent i2 = new Intent(MainActivity.this, GameDanska.class);
                i2.putExtra("myMethod", "nextQuestionHDPI");
                startActivity(i2);
            }

    }

Answer 1

按如下方式使用开关

Intent i = new Intent(this, GameDanska.class);

switch (getResources().getDisplayMetrics().densityDpi) {
    case DisplayMetrics.DENSITY_MEDIUM:
        i.putExtra("myMethod", "nextQuestionMDPI");
        startActivity(i);
        break;
    default:
        i.putExtra("myMethod", "nextQuestionHDPI");
        startActivity(i);
        break;
}

如果您的应用仅适用于 MDPI、HDPI、XHDPI，请记住将屏幕兼容性放在您的 manifest.xml 文件中。

<compatible-screens>
    <screen android:screenSize=["small" | "normal" | "large" | "xlarge"]
            android:screenDensity=["ldpi" | "mdpi" | "hdpi" | "xhdpi"] />
    ...
</compatible-screens>

就你的情况

 <compatible-screens>
    <screen android:screenSize="small" android:screenDensity="mdpi"/>
    <screen android:screenSize="small" android:screenDensity="hdpi"/>
    <screen android:screenSize="small" android:screenDensity="xhdpi"/>

    <screen android:screenSize="normal" android:screenDensity="mdpi"/>
    <screen android:screenSize="normal" android:screenDensity="hdpi"/>
    <screen android:screenSize="normal" android:screenDensity="xhdpi"/>

    <screen android:screenSize="large" android:screenDensity="mdpi"/>
    <screen android:screenSize="large" android:screenDensity="hdpi"/>
    <screen android:screenSize="large" android:screenDensity="xhdpi"/>

    <screen android:screenSize="xlarge" android:screenDensity="mdpi"/>
    <screen android:screenSize="xlarge" android:screenDensity="hdpi"/>
    <screen android:screenSize="xlarge" android:screenDensity="xhdpi"/>
 </compatible-screens>

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