我目前正在研究一個動畫來比較兩種股票交換算法。我在擴展JComponent的paint組件中運行算法。 (不是最好的,但我不在乎)我需要通過繪畫組件中途刷新屏幕。我不想讓它在日期顯示之前一路通過。原因是我有一個嵌套while循環的算法,另一個沒有。我會如何去做這件事?通過重塑使對象呈現一半
public void paintComponent(Graphics g) {
//calls in the super class and calls the calibrate the graphics method
super.paintComponent(g);
Graphics2D g2D = (Graphics2D) g;
calibrateFrame(getHeight(), getWidth());
//Clears the rectangle to avoid overlaying, makes it black
g2D.clearRect(0, 0, getWidth(), getHeight());
g2D.setColor(Color.BLACK);
g2D.fillRect(0, 0, getWidth(), getHeight());
//Draws the rectangles without the algorithm started
redraw(g2D, -1);
/**
*algorithms
*/
fastSpans[0] = 1;
slowSpans[0] = 1;
//Makes a new stack pushes 0 on the stack
Stack myStack = new Stack();
myStack.push(0);
//If it has not been sorted or paused, continue the algorithm
if (!(pause) && !(sorted)){
//The slower algorithm needs to start out at zero (j)
int j = indexValue-1;
g2D.setColor(Color.BLUE);
//Calculates the values for the X and Y coordinates for the
//new rectangle, along with the height
int slowY = calSlowY(j);
int slowX = calSlowX(j);
int curHeightSlow = (int) ((stocks[j]/maxStockValue)*maxHeight);
//Here is the actual algorithm
int k = 1;
boolean span_end = false;
//Nested While Loop
while (((j-k)>0) && !span_end){
if (stocks[j-k] <= stocks[j]){
k = k + 1;
// Draw the current component
// **********************
// DO REFRESH MID PAINT COMPONENT
}
else{ span_end = true; }
}
slowSpans[j] = k;
g2D.setColor(Color.WHITE);
for(int i = 0; i < numberOfStock ; i++){
}
if (!(indexValue >= numberOfStock)){
while (!(myStack.empty()) && (stocks[(int)myStack.peek()]) <= stocks[indexValue]){
myStack.pop();
}
if (myStack.empty()){
fastSpans[indexValue] = indexValue + 1;
}
else {
fastSpans[indexValue]= indexValue - (int) myStack.peek();
//System.out.println("Im in the else");
}
myStack.push(indexValue);
}
}
drawStrings(g2D);
}
你應該閱讀有關的繪畫系統是如何工作的[這裏](http://www.oracle.com/technetwork/java/painting-140037.html),然後用任何其他問題回來。對於所有的意圖和目的,你應該考慮paintComponent是一個原子操作。 –