Get SensorManager PowerManager WindowManager Display Android example

Unable to resolve target android-7
Try this solution:
Select project from tree (project explorer)
- right click on project
- properties
- select Android from tree
- change Project Build Target to higher (or change project build target)
- selct from menu: Project-Clean ( select your project - OK)

Dialog Yes No sample code

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Are you sure you want to exit application?")
       .setCancelable(false)
       .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
           public void onClick(DialogInterface dialog, int id) {
                MyActivity.this.finish(); //Close  this Activity for example: MyActivity.java
           }
       })
       .setNegativeButton("No", new DialogInterface.OnClickListener() {
           public void onClick(DialogInterface dialog, int id) {
                // some code if you want
                dialog.cancel();
           }
       });
AlertDialog alert = builder.create();
alert.show();

Example source code for Android Developers

// clickable TextView
public TextView createTextView(String sText, Context con){
 TextView b = null;
 try {
  b = new TextView (con);
  b.setTextSize(15.0f);
  b.setTextColor(Color.rgb( 0, 0, 200));
  b.setOnClickListener(this);
  b.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
  LayoutParams.WRAP_CONTENT));
  b.setText(sText);
  //tr.addView(b, 60,30);
  } catch (Exception e) {
  e.printStackTrace();
 return b;
 }
return b;
}
/*****************/
public void onClick(View view) {
 try {
  String s = ((TextView) view).getText().toString();
 }
 catch (Exception e1) {
   e1.printStackTrace();
 }
}
/***********/

// if you want restore in TextView after chagne of orientation
// you have to put  code to Manifest.xml android:configChanges

activity android:name=".main"
android:label="@string/app_name"
android:configChanges="keyboardHidden|orientation" //this line important !!!!!!!

Invalid proguard configuration file path
C:\documents\my_android_projects\my_project\proguard.cfg does not exist or is not a regular file

Solution:
Check if exist file proguard.cfg in your project on the path C:\docum.........
If not exist, copy a file proguard.cfg from other project or create file proguard.cfg and insert
this source code to file and save this file.

-optimizationpasses 5
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose
-optimizations !code/simplification/arithmetic,!field/*,!class/merging/*

-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider
-keep public class * extends android.app.backup.BackupAgentHelper
-keep public class * extends android.preference.Preference
-keep public class com.android.vending.licensing.ILicensingService

-keepclasseswithmembernames class * {
    native <methods>;
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet);
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet, int);
}

-keepclassmembers class * extends android.app.Activity {
   public void *(android.view.View);
}

-keepclassmembers enum * {
    public static **[] values();
    public static ** valueOf(java.lang.String);
}

-keep class * implements android.os.Parcelable {
  public static final android.os.Parcelable$Creator *;
}

From more details see:
//developer.android.com/guide/developing/tools/proguard.html

Difference between "@+id/” and "@id/” in Android
android:id="@+id/xxx" unique identifier of view
@id/ a reference to the unique identifier

 <TextView
        android:id="@+id/first_element_id"
        .........
 />
    <TextView
        android:id="@+id/second_element_id"
        android:layout_below="@id/first_element_id"
        ..........
 />