在Xamarin.Forms android中使用正确的屏幕高度和宽度的全局解决方案? [英] Global solution to use the correct screen height and width in Xamarin.Forms android?

问题描述

我正在使用Xamarin.Forms开发适用于Android和iOS平台的客户端的新应用程序，一切顺利，因为我决定在android平台中以不同屏幕尺寸查看该应用程序.

I'm developing a new app for a client with Xamarin.Forms for Android and iOS platforms, everything goes well since I decided review the app in different screen sizes in android platform.

看起来像Xamarin.Forms忽略了系统导航托盘，每个视图中的每个元素都显示在系统栏下方.我知道可以通过XAML.CS中的OnPlatform stament或SizeChanged事件来解决此问题，但是我想知道是否存在解决该问题的全局方法，而不是对每个页面进行少量修复.

Seems like Xamarin.Forms is ignoring the system navigation tray and every element in the each view appear under the system bar. I know this can be fixed with OnPlatform stament or SizeChanged event in the XAML.CS, but I want to know if exist a global approach to fix that issue instead making little fixes for each page.

看一看我的页面.

我的应用程序中几乎所有页面都用Grid完成，因此这里有3行，第二行有2列；在iOS页面中可以完美运行...但是在android系统中，这确实有点痛苦.

Almost all pages in my app are done with Grid, so here I have 3 rows, the second one with 2 columns; in iOS pages works perfectly... but android... it's a really somehow painful.

先谢谢了.

**从维护中添加的代码**

** ADDED CODE FROM MAINACTIVITY **

[Activity(Label = "MyBankingApp", Icon = "@drawable/icon", Theme = 
"@style/MainTheme", ConfigurationChanges = ConfigChanges.ScreenSize | 
ConfigChanges.Orientation, WindowSoftInputMode = SoftInput.AdjustResize,
          ScreenOrientation = ScreenOrientation.Portrait)]

我有以下三种方法:

    public void AndroidBug5497WorkaroundForXamarinAndroid () {

        FrameLayout content = (FrameLayout) this.FindViewById (Android.Resource.Id.Content);
        mChildOfContent = content.GetChildAt (0);
        ViewTreeObserver vto = mChildOfContent.ViewTreeObserver;
        vto.GlobalLayout += (object sender, EventArgs e) => {
            possiblyResizeChildOfContent ();
        };
        frameLayoutParams = (FrameLayout.LayoutParams) mChildOfContent.LayoutParameters;
    }

    private void possiblyResizeChildOfContent () {
        int usableHeightNow = computeUsableHeight ();
        if (usableHeightNow != usableHeightPrevious) {
            int usableHeightSansKeyboard = mChildOfContent.RootView.Height;
            int heightDifference = usableHeightSansKeyboard - usableHeightNow;

            frameLayoutParams.Height = usableHeightSansKeyboard - heightDifference;

            mChildOfContent.RequestLayout ();
            usableHeightPrevious = usableHeightNow;
        }
    }

    private int computeUsableHeight () {
        Android.Graphics.Rect r = new Android.Graphics.Rect ();
        mChildOfContent.GetWindowVisibleDisplayFrame (r);
        if (Build.VERSION.SdkInt < BuildVersionCodes.Lollipop) {
            return (r.Bottom - r.Top);
        }

        maxHeight = Math.Max(maxHeight, r.Bottom);
        return r.Bottom.Equals(maxHeight) ? maxHeight : (int)(maxHeight* 0.8);
    }

注意，我主要是iOS开发人员，因此有时我很难理解Android.

Notice I'm mainly iOS developer, so Android is a little hard to me to understand sometimes.

我的styles.xml

my styles.xml

<resources>
  <style name="MainTheme" parent="MainTheme.Base">
  </style>
  <!-- Base theme applied no matter what API -->
  <style name="MainTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">
    <!--If you are using revision 22.1 please use just windowNoTitle. Without android:-->
    <item name="windowNoTitle">true</item>
    <!--We will be using the toolbar so no need to show ActionBar-->
    <item name="windowActionBar">false</item>
    <!-- Set theme colors from http://www.google.com/design/spec/style/color.html#color-color-palette -->
    <!-- colorPrimary is used for the default action bar background -->
    <item name="colorPrimary">#181F27</item>
    <!-- colorPrimaryDark is used for the status bar -->
    <item name="colorPrimaryDark">#181F27</item>
    <!-- colorAccent is used as the default value for colorControlActivated
         which is used to tint widgets -->
    <item name="colorAccent">#7FAD30</item>
    <!-- You can also set colorControlNormal, colorControlActivated
         colorControlHighlight and colorSwitchThumbNormal. -->
    <item name="windowActionModeOverlay">true</item>
    <item name="android:datePickerDialogTheme">@style/AppCompatDialogStyle</item>
  </style>
  <style name="AppCompatDialogStyle" parent="Theme.AppCompat.Light.Dialog">
    <item name="colorAccent">#7FAD30</item>
  </style>
     <style name="MyTheme.Splash" parent ="Theme.AppCompat.Light.NoActionBar">
    <item name="android:windowBackground">@drawable/splashbg</item>
    <item name="android:windowNoTitle">true</item>  
    <item name="android:windowFullscreen">true</item>  
    <item name="android:windowContentOverlay">@null</item>  
    <item name="android:windowActionBar">true</item>  
  </style>
</resources>

推荐答案

• 在您的Android项目中添加以下主题:

values/styles.xml

<?xml version="1.0" encoding="utf-8" ?>
<resources>
<style name="MyTheme" parent="MyTheme.Base">
</style>

<style name="DrawerArrowStyle" 
parent="@style/Widget.AppCompat.DrawerArrowToggle">
<item name="spinBars">true</item>
 <item name="color">#FFFFFF</item>
</style>

<style name="MyTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">
<item name="windowNoTitle">true</item>
<item name="windowActionBar">false</item>
<item name="colorPrimary">#003399</item>
<item name="colorPrimaryDark">#003399</item>
<item name="colorControlHighlight">#003399</item>
<item name="colorAccent">#012348</item>
<item name="drawerArrowStyle">@style/DrawerArrowStyle</item>
</style>

</resources>

• 创建一个名为values-v21的文件夹，并添加一个名为styles.xml的XML，并向其中添加以下代码:

  • Create a folder named values-v21 and add an XML named styles.xml and add the following code to it :

     <?xml version="1.0" encoding="utf-8" ?>
     <resources>
     <style name="MyTheme" parent="MyTheme.Base">
     <item name="android:windowContentTransitions">true</item>
     <item name="android:windowAllowEnterTransitionOverlap">true</item>
     <item name="android:textAllCaps">false</item>
     <item name="android:windowAllowReturnTransitionOverlap">true</item>
     <item name="android:windowSharedElementEnterTransition">@android:transition/move</item>
     <item name="android:windowSharedElementExitTransition">@android:transition/move</item>
     </style>
     </resources>
    

  并在所有Android活动中使用名称myTheme作为应用程序主题:

  And use the name myTheme as the app theme in all your Android activities:

  类似这样的东西:

  [Activity(Label = "MyBankingApp", Icon = "@drawable/icon", Theme = "@style/MyTheme", ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation, WindowSoftInputMode = SoftInput.AdjustResize, ScreenOrientation = ScreenOrientation.Portrait)]
  

  在不起作用的情况下还原

  Revert in case it doesn't work

  这篇关于在Xamarin.Forms android中使用正确的屏幕高度和宽度的全局解决方案?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！