choicegrouplfimpl.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 621 行 · 第 1/2 页

     * is selected or not.
     * @param elementNum the index of an element in question
     * @return true if the element is selected, false - otherwise
     */
    public boolean lIsSelected(int elementNum) {
        if (nativeId == DisplayableLFImpl.INVALID_NATIVE_ID) {
            return cg.cgElements[elementNum].selected;
        }
        
        return isSelected0(nativeId, elementNum);
    }

    // *****************************************************
    //  Package private methods
    // *****************************************************

    /**
     * Called by event delivery to notify an ItemLF in current FormLF
     * of a change in its peer state.
     *
     * @param hint index of the element whose selection status has changed
     * @return always true so ItemStateListener should be notified
     */
    boolean uCallPeerStateChanged(int hint) {
	// Any hint means selection has change
	// For types other than IMPLICIT List, notify itemStateListener.
	if (cg.choiceType != Choice.IMPLICIT) {
	    return true; // notify itemStateListener
	}

	// For IMPLICIT List, notify commandListener
	List list;
	CommandListener cl;
	Command cmd;

	synchronized (Display.LCDUILock) {
	    list = (List)cg.owner;

	    if (list.listener == null ||
		list.selectCommand == null ||
		cg.numOfEls == 0) {
		return false; // No itemStateListener to notify
	    }

	    cl = list.listener;
	    cmd = list.selectCommand;
	}
	
	try {
	    synchronized (Display.calloutLock) {
		cl.commandAction(cmd, list);
	    }
	} catch (Throwable thr) {
	    Display.handleThrowable(thr);
	}

	return false; // No itemStateListener to notify
    }

    /**
     * Determine if this Item should have a newline after it
     *
     * @return true if it should have a newline after
     */
    boolean equateNLA() {
        if (super.equateNLA()) {
            return true;
        }
        return ((cg.layout & Item.LAYOUT_2) != Item.LAYOUT_2);
    }


    /**
     * Determine if this Item should have a newline before it
     *
     * @return true if it should have a newline before
     */
    boolean equateNLB() {
        if (super.equateNLB()) {
            return true;
        }

        return ((cg.layout & Item.LAYOUT_2) != Item.LAYOUT_2);
    }

    /**
    /**
     * Override <code>ItemLFImpl</code> method to sync with native resource
     * before hiding the native resource. Selection of native resource will 
     * be preserved before the resource is hidden.
     */
    void lHideNativeResource() {
	// sync selected flags and selectedIndex
	// before any visible native resource is deleted.
	if (nativeId != DisplayableLFImpl.INVALID_NATIVE_ID) {
	    syncSelectedIndex();
	    syncSelectedFlags();
	}

	// Hide native resource
        super.lHideNativeResource();
    }

    /**
     * Creates and sets  native resource for current ChoiceGroup.
     * Override function in ItemLFImpl.
     * @param ownerId Owner screen's native resource id
     */
    void createNativeResource(int ownerId) {
        nativeId = createNativeResource0(ownerId, cg.label, 
					 (cg.owner instanceof List ? 
					  -1 : cg.layout),
                                         cg.choiceType, cg.fitPolicy, 
                                         cg.cgElements, cg.numOfEls, 
                                         selectedIndex);
    }

    // *****************************************************
    //  Private methods
    // *****************************************************

    /**
     * Read and save user selection from native resource.
     */
    private void syncSelectedIndex() {
        if (cg.choiceType != Choice.MULTIPLE) {
            int newSelectedIndex = getSelectedIndex0(nativeId);
            if (selectedIndex != newSelectedIndex) {
                if (selectedIndex != -1) {
                    cg.cgElements[selectedIndex].setSelected(false);
                }
                selectedIndex = newSelectedIndex;
                if (selectedIndex != -1) {
                    cg.cgElements[selectedIndex].setSelected(true);
                }
            }
        }
    }

    /**
     * Read and save user selection from native resource.
     */
    private void syncSelectedFlags() {
        if (cg.numOfEls > 0 && cg.choiceType == Choice.MULTIPLE) {
            boolean[] selectedArray_return = new boolean[cg.numOfEls];
            
            getSelectedFlags0(nativeId, selectedArray_return,
                              cg.numOfEls);
            
            for (int i = 0; i < cg.numOfEls; i++) {
                cg.cgElements[i].setSelected(selectedArray_return[i]);
            }
        }
    }

    /**
     * KNI function that creates native resource for current ChoiceGroup.
     * @param ownerId Owner screen's native resource id (MidpDisplayable *)
     * @param label string to be used as label for this ChoiceGroup
     * @param layout layout directive associated with this <code>Item</code>
     * @param choiceType should be EXCLUSIVE, MULTIPLE, IMPLICIT, POPUP
     * @param fitPolicy should be TEXT_WRAP_DEFAULT, TEXT_WRAP_ON, or
     *                    TEXT_WRAP_OFF
     * @param cgElements array of CGElement that stores such data as
     *                   image, text, font, selection state per element
     * @param numChoices number of valid elements in cgElements array
     * @param selectedIndex index of a currently selected element
     *                      (has no meaning for MULTIPLE ChoiceGroup)
     * @return native resource id (MidpItem *) of this ChoiceGroup
     */
    private native int createNativeResource0(int ownerId, String label, 
					     int layout,
                                             int choiceType, int fitPolicy,
                                             CGElement []cgElements,
                                             int numChoices,
                                             int selectedIndex);


    /**
     * KNI function that notifies native resource of a new element
     * inserted prior to the element specified
     * 
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element where insertion is to occur
     * @param stringPart the string part of the element to be inserted
     * @param imagePart the image part of the element to be inserted
     * @param selected the selected state of the element to be inserted
     */
    private native void insert0(int nativeId, int elementNum, 
                                String stringPart, ImageData imagePart,
                                boolean selected);

    /**
     * KNI function that notifies native resource of a specified element
     * being deleted in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element to be deleted
     * @param selectedIndex the index of an element to be selected after the
     *        deletion is done (has no meaning for MULTIPLE ChoiceGroup)
     */
    private native void delete0(int nativeId, int elementNum, 
                                int selectedIndex); 

    /**
     * KNI function that notifies native resource that all elements were
     * deleted in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     */
    private native void deleteAll0(int nativeId);

    /**
     * KNI function that notifies native resource of a specified element
     * being set in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element to be set
     * @param stringPart the string part of the element to be set
     * @param imagePart the image part of the element to be set
     * @param selected the selected state of the element to be set
     */
    private native void set0(int nativeId, int elementNum, 
                             String stringPart, ImageData imagePart, 
                             boolean selected);

    /**
     * KNI function that notifies native resource of an element's new selected
     * state in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element which selected state changed
     * @param selected the new selected state
     */
    private native void setSelectedIndex0(int nativeId, int elementNum,
                                          boolean selected);
    /**
     * KNI function that notifies native resource of new selected
     * states in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param selectedArray array with new selected states
     * @param numSelectedArray number of elements in selectedArray to be used
     */
    private native void setSelectedFlags0(int nativeId, 
                                          boolean []selectedArray,
                                          int numSelectedArray);
    /**
     * KNI function that notifies native resource of fit policy change
     * in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param fitPolicy new fit policy (can be TEXT_WRAP_OFF, TEXT_WRAP_ON,
     *                  or TEXT_WRAP_DEFAULT)
     */
    private native void setFitPolicy0(int nativeId, int fitPolicy);

    /**
     * KNI function that notifies native resource of an element's new font
     * setting in the corresponding ChoiceGroup.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element which font has changed
     * @param face of the newly set font
     * @param style of the newly set font 
     * @param size of newly set font
     */
    private native void setFont0(int nativeId, int elementNum,
                                 int face, int style, int size);

    /**
     * KNI function that gets index of a currently selected index from 
     * the ChoiceGroup's native resource.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @return index of the currently selected element
     */
    private native int getSelectedIndex0(int nativeId);

    /**
     * KNI function that queries the state of all elements in the native
     * resource and returns it in the passed in selectedArray array.
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param selectedArray to contain the results
     * @param numOfEls number of elements in selectedArray
     * @return the number of elements selected in the native resource
     */
    private native int getSelectedFlags0(int nativeId, 
                                         boolean[] selectedArray,
                                         int numOfEls);
    /**
     * KNI function that queries the state of an element in the native
     * resource
     *
     * @param nativeId native resource id (MidpItem *) of this ChoiceGroup
     * @param elementNum the index of an element which state is queried
     * @return the current state of an element in the nativer resource
     */
    private native boolean isSelected0(int nativeId, int elementNum);

    /** ChoiceGroup associated with this ChoiceGroupLF. */
    ChoiceGroup cg;

    /**
     * The currently selected index of this ChoiceGroup (-1 by default).
     */
    int selectedIndex = -1;
}