getränte klassen nach gerätetype

Ich möchte nocheinmal auf das altbekannte thema Display Größen zurückkommen. Es geht darum, dass ich zwei verschidenen Klassen aufrufen möchte, jenachdem ob der App auf einem Tablet oder auf einem Handy leuft. Dazu würde ich gerne eine booleme variable bei programmstart definieren.

if ([smallestWidth > 480) { IfTab = true; }

Wie finde ich heraus ob mein App auf einem Tab oder einem Handy leuft?

In der Doku habe ich folgende Seite gefunden: Rroviding Resources
In der Tabelle "Table 2. Configuration qualifier names." werden alle Möglichkeiten aufgeführt.
Am brauchbarsten scheint mir hier folgende Methode: smallestWidth. Ich zitiere:
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"Qualifier Values:
sw<N>dp

Examples:
sw320dp
sw600dp
sw720dp
etc.
Description
The fundamental size of a screen, as indicated by the shortest dimension of the available screen area. Specifically, the device's smallestWidth is the shortest of the screen's available height and width (you may also think of it as the "smallest possible width" for the screen). You can use this qualifier to ensure that, regardless of the screen's current orientation, your application's has at least <N> dps of width available for it UI.

For example, if your layout requires that its smallest dimension of screen area be at least 600 dp at all times, then you can use this qualifer to create the layout resources, res/layout-sw600dp/. The system will use these resources only when the smallest dimension of available screen is at least 600dp, regardless of whether the 600dp side is the user-perceived height or width. The smallestWidth is a fixed screen size characteristic of the device; the device's smallestWidth does not change when the screen's orientation changes.

The smallestWidth of a device takes into account screen decorations and system UI. For example, if the device has some persistent UI elements on the screen that account for space along the axis of the smallestWidth, the system declares the smallestWidth to be smaller than the actual screen size, because those are screen pixels not available for your UI. Thus, the value you use should be the actual smallest dimension required by your layout (usually, this value is the "smallest width" that your layout supports, regardless of the screen's current orientation).

Some values you might use here for common screen sizes:

320, for devices with screen configurations such as:
240x320 ldpi (QVGA handset)
320x480 mdpi (handset)
480x800 hdpi (high density handset)
480, for screens such as 480x800 mdpi (tablet/handset).
600, for screens such as 600x1024 mdpi (7" tablet).
720, for screens such as 720x1280 mdpi (10" tablet).
When your application provides multiple resource directories with different values for the smallestWidth qualifier, the system uses the one closest to (without exceeding) the device's smallestWidth.

Added in API level 13.
"

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Diese Angaben beziehen sich jetzt aber auf die XML Datei. Kann ich darauf auch im Programm zugreifen??

Ich bräuchte quasie folgenden Text in Java und nicht in der ordner Struktur:

res/layout/main_activity.xml           # For handsets (smaller than 600dp available width)
res/layout-sw600dp/main_activity.xml   # For 7” tablets (600dp wide and bigger)
res/layout-sw720dp/main_activity.xml   # For 10” tablets (720dp wide and bigger)

Zitat von UweApps

Mit den Parametern und ein bisschen rumrechnen hast du dann die Bedingungen für dein if und kannst deine Activities starten.

OK, dass rumrechnen:

DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int met= metrics.widthPixels;

Das Ergebniss:

metrics=DisplayMetrics{density=1.0, width=320, height=480, scaledDensity=1.0, xdpi=160.0, ydpi=160.0}
met=320

Jetzt kann ich einen dieser Werte für die IF schleife nehmen. Welchen würdest du mir empfehlen?

public float density The logical density of the display.
public int densityDpi The screen density expressed as dots-per-inch.
public int heightPixels The absolute height of the display in pixels.
public float scaledDensity A scaling factor for fonts displayed on the display.
public int widthPixels The absolute width of the display in pixels.
public float xdpi The exact physical pixels per inch of the screen in the X dimension.
public float ydpi The exact physical pixels per inch of the screen in the Y dimension.

Ich glaube widthPixels ist dass beste, oder ?