編輯:關於android開發
做基於WebView應用時,頁面上有一個輸入框,當輸入的文字過多時,超過輸入框的行數時,輸入框能夠滾動,這時間問題來了,輸入的提示箭頭會移動到輸入框外,如何解決這個問題呢,查找chromium源碼如下:
void LoadIfNecessary(jobject context) {
if (loaded_)
return;
loaded_ = true;
TRACE_EVENT0("browser", "HandleResources::Create");
JNIEnv* env = base::Android::AttachCurrentThread();
if (!context)
context = base::android::GetApplicationContext();
left_bitmap_ = CreateSkBitmapFromJavaBitmap(
Java_HandleViewResources_getLeftHandleBitmap(env, context));
right_bitmap_ = CreateSkBitmapFromJavaBitmap(
Java_HandleViewResources_getRightHandleBitmap(env, context));
center_bitmap_ = CreateSkBitmapFromJavaBitmap(
Java_HandleViewResources_getCenterHandleBitmap(env, context));
left_bitmap_.setImmutable();
right_bitmap_.setImmutable();
center_bitmap_.setImmutable();
drawable_horizontal_padding_ratio_ =
Java_HandleViewResources_getHandleHorizontalPaddingRatio(env);
}
這個函數加載這幾個圖片,在java端,
private static Bitmap getHandleBitmap(Context context, final int[] attrs) {
// TODO(jdduke): Properly derive and apply theme color.
TypedArray a = context.getTheme().obtainStyledAttributes(attrs);
final int resId = a.getResourceId(a.getIndex(0), 0);
final Resources res = a.getResources();
a.recycle();
final Bitmap.Config config = Bitmap.Config.ARGB_8888;
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = false;
options.inPreferredConfig = config;
Bitmap bitmap = BitmapFactory.decodeResource(res, resId, options);
savePic( bitmap);
if (bitmap != null) return bitmap;
// If themed resource lookup fails, fall back to using the Context's
// resources for attribute lookup.
if (res != context.getResources()) {
bitmap = BitmapFactory.decodeResource(context.getResources(), resId, options);
if (bitmap != null) return bitmap;
}
Drawable drawable = getHandleDrawable(context, attrs);
assert drawable != null;
final int width = drawable.getIntrinsicWidth();
final int height = drawable.getIntrinsicHeight();
Bitmap canvasBitmap = Bitmap.createBitmap(width, height, config);
Canvas canvas = new Canvas(canvasBitmap);
drawable.setBounds(0, 0, width, height);
drawable.draw(canvas);
return canvasBitmap;
}
C++中會調用java中的函數getHandleBitmap,這個函數通過 context.getTheme().obtainStyledAttributes 這個函數,從jdk中加載圖片資源,顯示時,通過GetBitmap函數獲取到圖像信息,通過layer_->SetBitmap( bitmap)設置顯示的內容,函數如下:
const SkBitmap& GetBitmap(ui::TouchHandleOrientation orientation) {
DCHECK(loaded_);
switch (orientation) {
case ui::TouchHandleOrientation::LEFT:
return left_bitmap_;
case ui::TouchHandleOrientation::RIGHT:
return right_bitmap_;
case ui::TouchHandleOrientation::CENTER:
return center_bitmap_;
case ui::TouchHandleOrientation::UNDEFINED:
NOTREACHED() << "Invalid touch handle orientation.";
};
return center_bitmap_;
}
這麼分析下來,想從顯示下手解決這個問題,似乎不太可能,那只有替換圖片資源,而圖像資源是在android.jar包中,還有其他辦法嗎? 分析源碼,
public static Drawable getLeftHandleDrawable(Context context) {
return getHandleDrawable(context, LEFT_HANDLE_ATTRS);
}
public static Drawable getCenterHandleDrawable(Context context) {
return getHandleDrawable(context, CENTER_HANDLE_ATTRS);
}
public static Drawable getRightHandleDrawable(Context context) {
return getHandleDrawable(context, RIGHT_HANDLE_ATTRS);
}
有這幾個圖像id 信息,是不是可以重載呢,於是添加自己的
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="MyTheme">
<item name="android:textSelectHandleLeft">@drawable/ic_launcher</item>
<item name="android:textSelectHandle">@drawable/aa</item>
<item name="android:textSelectHandleRight">@drawable/ic_launcher</item>
</style>
</resources>
替換掉系統的資源,再添加android:theme="@style/MyTheme" 自己的主題風格,問題解決
推薦:http://www.cnblogs.com/roucheng/p/androidservice.html
Android筆記——Android中數據的存儲方式(三),android筆記 Android系統集成了一個輕量級的數據庫:SQLite,所以Android對數據庫的支
Android4.4訪問外部存儲,android4.4訪問存儲 在Android 4.4系統中,外置存儲卡(SD卡)被稱為二級外部存儲設備(secondary
git 上的pull request 是什麼意思?,gitpull 1、git 上有常見的pull request 功能  
Android Studio創建/打開項目時一直處於Building“project name”Gradle project info的解決辦法,androidgradl