Draw Arc Android basic example
drawArc(), Canvas, Paint, setStyle()
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
// CONSTRUCTOR
public SampleView(Context context) {
super(context);
setFocusable(true);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.CYAN);
Paint p = new Paint();
// smooths
p.setAntiAlias(true);
p.setColor(Color.RED);
p.setStyle(Paint.Style.STROKE);
p.setStrokeWidth(5);
// opacity
//p.setAlpha(0x80); //
RectF rectF = new RectF(50, 20, 100, 80);
canvas.drawOval(rectF, p);
p.setColor(Color.BLACK);
canvas.drawArc (rectF, 90, 45, true, p);
}
}
}
396LW NO topic_id
AD
Další témata ....(Topics)
// file name MyFirstClass.java
import java.util.*;
import java.lang.Math;
import java.io.*;
import javax.swing.*;
public class MyFirstClass{ // start of program
public static void main(String[] args) { // basic function main
// variables and calculation
int a=2;
int b=3;
int c=Integer.parseInt(JOptionPane.showInputDialog(" Put number: ", "1"));
System.out.println("Number is: "+c);
System.out.println(a+" * "+b+" = "+(a*b));
System.out.println("a^3 "+Math.pow(a,b));
//array
int[] array_my=new int[10];
array_my[0]=3;
array_my[1]=5;
System.out.println("Number of elements "+array_my.length+" 1 + 2 element of array "+(array_my[0]+array_my[1]));
//strings
String txt="Quick red fox";
String txt2=JOptionPane.showInputDialog("Write text: ", "word");
System.out.println("Text is: "+txt2);
String[] count_of_word=txt.split(" ");
System.out.println("Length: "+txt.length()+" Count of words "+count_of_word.length);
System.out.println(txt +" -> "+txt.replace("red","brown"));
System.out.println("First 5 chars of string is: "+ txt.substring(0,5));
//for a if
for(int i=0; i<10;i++){
if(i==3)System.out.println("i equal "+i);
}
// file
try {
File soubor=new File("some_file.txt");
if(!soubor.exists()){
System.out.println("File dont exist");
}
else { // utf-8 encoding
BufferedReader in1 = new BufferedReader(new InputStreamReader(new FileInputStream(soubor),"UTF-8"));
BufferedWriter out1 = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("zapis.txt"),"UTF-8"));
String str;
while ((str = in1.readLine())!=null){
System.out.println(str);
out1.write(str+"
");
}
in1.close();
out1.close();
}
} catch(IOException e){System.out.println("Error " + e);}
// dir
File pathName = new File("some_dir");
String[] fileNames = pathName.list();
if(pathName.exists())
System.out.println("Name of first file in "some_dir": "+fileNames[0]);
else System.out.println("dir not exist");
//function
int nResult = calculateMyFc(3,5);
System.out.println("Result of function: "+nResult);
} // end of function main
// new function , you can add to end MyFc = my function
public static int calculateMyFc(int a, int b){
return (a+b);
}
} // end of class of program
xml example source code with image.
<TableLayout android:layout_width="match_parent" android:id="@+id/idTableInRadioGroup" android:layout_height="wrap_content">
<TableRow android:id="@+id/tableRow1" android:layout_width="wrap_content" android:layout_height="wrap_content">
<RadioGroup android:id="@+id/idRadio_group_1_column"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:orientation="vertical">
<RadioButton android:id="@+id/idRadio_1"
android:text="@string/textLabel_1"/>
<RadioButton android:id="@+id/idRadio_2"
android:text="@string/textLabel_2"/>
<RadioButton android:id="@+id/idRadio_3"
android:text="@string/textLabel_3"/>
</RadioGroup>
<RadioGroup android:id="@+id/idRadio_group_2_column"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:orientation="vertical">
<RadioButton android:id="@+id/idRadio_4"
android:text="@string/textLabel_4"/>
<RadioButton android:id="@+id/idRadio_5"
android:text="@string/textLabel_5"/>
<RadioButton android:id="@+id/idRadio_6"
android:text="@string/textLabel_6"/>
</RadioGroup>
</TableRow>
</TableLayout>
Video tutorial
How to add or remove widgets home screen Android 4.
How to add or remove widgets home screen Android 4.
If you want download some *.apk file from internet and try on your emulator you get error than you have to install SD card. You have to closing Android emulator.
Mount Android emulator SD card instruction
Image how install SD card on Android emulator in Eclipse.
Mount Android emulator SD card instruction
- In Eclipse go in menu Window - Android SDK and Avg Manager
- Select Virtual devices
- Select AVD Name where you need install SD card
- Click on Edit button
- In open dialog go to SD card - Size: and write 500
- Press button Edit AVD
- Run AVD emulator
Image how install SD card on Android emulator in Eclipse.
Solution:
public void alertMy(String sTitle, String sMessage){
AlertDialog.Builder builder = new AlertDialog.Builder(Test.this); // activity
builder.setTitle(sTitle)
.setMessage(sMessage)
.setCancelable(false)
.setNegativeButton("Close",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.show();
}
Editace: 2013-12-09 13:11:05
Počet článků v kategorii: 396
Url:draw-arc-android-basic-example