File open read to StringBuilder close Java example

BufferedReader , FileReader, StringBuilder , readLine, close Java example

Android example


String MYFILE = "my_file";
FileInputStream fis = openFileInput(MYFILE);
	int c; String sText = "";
	while((c=fis.read())!=-1)
	{

		sText += (char)c; // convert int to char
	 }
	fis.close();

Java example


try {
	    BufferedReader in = new BufferedReader(new FileReader("myfile.txt"));
	    StringBuilder strBuilder = new StringBuilder();
	    String str;
	    while ((str = in.readLine()) != null) {
	       strBuilder.append(str);
	    }
	    in.close();
	} catch (IOException e) {
		e.toString();
	}

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331

Lenovo A6000 smartphone pictures from camera 8mpx review | lenovo-a6000-smartphone-pictures-from-camera-8mpx

Pictures taken by front camera Lenovo A6000 smartpohone - review.
Do not take pictures against the sun.
Stay in the shade. Keep lens clean.

Night without flash

Misty - smog

Without flash in room - TV screen

android/podzamecka-zahrada-kromeriz-lenovo-a6000-1_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-2_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-3_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-4_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-5_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-6_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-7_t.jpg

android/podzamecka-zahrada-kromeriz-lenovo-a6000-8_t.jpg

How to make a quick start the android emulator | how-to-make-a-quick-start-the-android-emulator

Very very quick start of Android Emulator from Eclipse.

Go to Eclipse s menu Window -> Android SDK and AVD Manager

Select Virtual devices

Select check box Snapshot: Enabled

Press Edit AVD button.

If will closed Android Emulator all data will saved on disk.
If will reopen Android Emulator, configuration and data will read from disk.

[caption id="attachment_768" align="alignleft" width="300" caption="android-emulator-enable-quick-start"]

android/android-emulator-quick-start-300x247.png

[/caption]

364

layout-sw600dp values-sw600dp Android example of use | layout-sw600dp-values-sw600dp-android-example-of-use

Why the app selects data from basic layout folder if smallest width is higher then the number in folder name?
Example 1
layout-sw600dp values-sw600dp (smallest width sw for data usage from this folder is 600dp density independent pixel!!!!!)
Device screen resolution is 1200 x 900 px (pixel) Wow, app to be select data from sw600dp folder! Realy?
DPI of device screen - dot per inch (pixel per inch) is 480 pixel it is wery important number!

App selects smallest dimension of screen. In our case 900 px
Medium screen have 160 dpi (The density-independent pixel is equivalent to one physical pixel on a 160 dpi screen, which is the baseline density assumed by the system for a "medium" density screen.).

App calculate ratio 480 / 160 = 3 (The conversion of dp units to screen pixels: px = dp * (dpi / 160))

App calculate smallest dimesnion of screen in dp 900 / 3 = 300 dip or dp (density independed pixel).

App selects data from basic values and layout folder because sw600dp is greater than 300dp.

In our case smallest dimension of screen must be at least 1800 real - physical pixels (1800 px / 3 ratio(dpi/160) = 600 dp (dip density independend pixels) to be used data from folders values-sw600dp and layout-sw600dp.

Example 2 see Example 1 abouve
Device: Nexus 7 (2012) selected from Android Studio tool layout editor
Resolution: 800x1280 px
DPI: tvdpi (approximately 213dpi)
Ratio: 1.33 (213 / 160)
Smallest width in px: 800
Convert px to dp: 601.5 (800 / 1.33)
Result:Smallest width is 601.5dp The App to be used data from folders values-sw600dp and layout-sw600dp.

274

SD card SDcard get external storage directory Android | sd-card-get-external-storage-directory-android

Environment.getExternalStorageDirectory()+ File.separator


Boolean canWrite =	Environment.getExternalStorageDirectory().canWrite() ;
if(canWrite){
File f = new File(Environment.getExternalStorageDirectory()
                        + File.separator + "my_image.jpg")
f.createNewFile();
}else{

}

AndroidManifest.xml

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

187

Error android.widget.LinearLayout.measureHorizontal LinearLayout.java | error-android-widget-linearlayout-measurehorizontal-linearlayout-java

Code with error:


ImageView imgV = (ImageView)findViewById(R.id.myView);
        imgV.setLayoutParams(new ViewGroup.LayoutParams(
        		ViewGroup.LayoutParams.WRAP_CONTENT,
        		0));

If you get error try this code:


        ViewGroup.LayoutParams layoutParams = imgV
				.getLayoutParams();
		layoutParams.height = 0;
		imgV.setLayoutParams(layoutParams);

java.lang.ClassCastException: android.view.ViewGroup$LayoutParams
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:659)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:311)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:386)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:531)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)

Editace: 2011-10-03 12:34:27
Počet článků v kategorii: 396
Url:file-open-read-to-stringbuilder-close-java-example