One of the methods that we can use is to create a similar component, by utilizing existing component. A Number Picker component consist of two buttons and one view / textview component. First button is to decrement/ get previous value from value array. Second button is to increment the value / get next value from value array. And lastly, textview componet to display the current selected value.
Three existing components (2 buttons, 1 textview), can be wrapped together in a viewgroup component like LinearLayout. and we can make a method to handle for clicking/touching the button.
As the title said, the class we defined can be use also as a Text Picker (Spinner substitution). While spinner show a dialog when fetching new value, this component can show directly without using new dialog to show the choice items.
Picture below, is an example of using this custom component in a dialog:
Ok, let's show the code that you can use
public class ValueSpinner extends LinearLayout {
public static final int NUMBER= 0;
public static final int TEXT = 1;
private int style=0;
private TextPaint paint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
private int min=0;
private int max=100;
private ArrayList valueString=new ArrayList();
private int value=0;
//---
Button incButton;
Button decButton;
TextView valueView;
public ValueSpinner(Context context) {
super(context);
init();
}
public ValueSpinner(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public ValueSpinner(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
decButton = new Button(getContext());
valueView = new TextView(getContext());
incButton = new Button(getContext());
this.addView(decButton, new MarginLayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
this.addView(valueView, new MarginLayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
this.addView(incButton, new MarginLayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
valueView.setText(getValueString());
valueView.setTextSize(20);
valueView.setGravity(Gravity.CENTER);
paint.setTextSize(valueView.getTextSize());
reCalculateWidthAndCaption();
decButton.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN) {
touchSet(0);
}
return false;
}
});
incButton.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN) {
touchSet(1);
}
return false;
}
});
}
protected void touchSet(int i) {
int p = i ^ getOrientation();
switch(p) {
case 0:
value--;
break;
case 1:
value++;
break;
}
value = value < min ? min : value > max ? max : value;
valueView.setText(getValueString());
invalidate();
}
@Override
public void setOrientation(int orientation) {
super.setOrientation(orientation);
reCalculateWidthAndCaption();
}
private String getValueString() {
String ret = "";
switch(style) {
case NUMBER:
ret = String.valueOf(value);
break;
case TEXT:
try {
ret = valueString.get(value) == null ? "" : valueString.get(value);
} catch (Exception e) {
ret = "";
}
break;
}
return ret;
}
public int getStyle() {
return style;
}
private void reCalculateWidthAndCaption() {
MarginLayoutParams lp = (MarginLayoutParams) valueView.getLayoutParams();
lp.width = (int) StaticLayout.getDesiredWidth(" WWW ", paint) ;
if (valueString.size()>0) {
String s="";
for(int i=0; i < valueString.size(); i++) {
s = s.length() > valueString.get(i).length() ? s : valueString.get(i);
}
int w = (int) StaticLayout.getDesiredWidth(s, paint);
lp.width = w > lp.width ? w : lp.width;
}
switch(getOrientation()) {
case LinearLayout.HORIZONTAL:
decButton.setText("-");
incButton.setText("+");
lp.width += 10;
lp.leftMargin = 5;
lp.rightMargin= 5;
break;
case LinearLayout.VERTICAL:
decButton.setText("+");
incButton.setText("-");
lp.height = 60;
lp.topMargin= 5;
lp.bottomMargin= 5;
break;
}
valueView.setText(getValueString());
}
public void setStyle(int style) {
this.style = style;
reCalculateWidthAndCaption();
}
public int getMin() {
return min;
}
public void setMin(int min) {
this.min = min;
value = value < min ? min : value;
}
public int getMax() {
return max;
}
public void setMax(int max) {
this.max = max;
value = value > max ? max : value;
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
valueView.setText(getValueString());
}
public void setValueString(String[] valueString) {
if (valueString==null)
return;
if (valueString.length==0)
return;
this.valueString.clear();
for (int i=0; i< valueString.length; i++)
this.valueString.add(valueString[i]);
this.min =0;
this.max = this.valueString.size()-1;
this.value=0;
this.style=TEXT;
reCalculateWidthAndCaption();
}
public void setValueString(ArrayList valueString) {
if (valueString==null)
return;
if (valueString.size()==0)
return;
this.valueString=valueString;
this.min =0;
this.max = this.valueString.size()-1;
this.value=0;
this.style=TEXT;
reCalculateWidthAndCaption();
}
public void setNextBackgroundResource(int background) {
incButton.setBackgroundResource(background);
MarginLayoutParams lp = (MarginLayoutParams) incButton.getLayoutParams();
incButton.setText("");
lp.width=50;
lp.height=50;
}
public void setPrevBackgroundResource(int background) {
decButton.setBackgroundResource(background);
MarginLayoutParams lp = (MarginLayoutParams) decButton.getLayoutParams();
decButton.setText("");
lp.width=50;
lp.height=50;
}
}
ok, Have a nice try!
Do you want to learn more ?
Learning with sample code ?
Learning by Doing ?
Just Visit http://learncodes.googlepages.com/
0 comments:
Post a Comment