GuiScrollSlot.java

package codechicken.core.gui;

import org.lwjgl.input.Keyboard;

import java.awt.*;

public abstract class GuiScrollSlot extends GuiScrollPane {
    protected String actionCommand;
    public boolean focused;
    protected ClickCounter<Integer> click = new ClickCounter<Integer>();
    public boolean smoothScroll = true;

    public GuiScrollSlot(int x, int y, int width, int height) {
        super(x, y, width, height);
        setMargins(3, 2, 3, 2);
    }

    public GuiScrollSlot setActionCommand(String s) {
        actionCommand = s;
        return this;
    }

    public void setSmoothScroll(boolean b) {
        smoothScroll = b;
    }

    public abstract int getSlotHeight(int slot);

    protected abstract int getNumSlots();

    public void selectNext() {
    }

    public void selectPrev() {
    }

    /**
     * Coordinates are relative to slot area
     */
    protected abstract void slotClicked(int slot, int button, int mx, int my, int count);

    protected abstract void drawSlot(int slot, int x, int y, int mx, int my, float frame);

    protected void unfocus() {
    }

    public void setFocused(boolean focus) {
        focused = focus;
        if (!focused) {
            unfocus();
        }
    }

    @Override
    public int contentHeight() {
        return getSlotY(getNumSlots());
    }

    public int getSlotY(int slot) {
        int h = 0;
        for (int i = 0; i < slot; i++) {
            h += getSlotHeight(i);
        }
        return h;
    }

    public int getSlot(int my) {
        if (my < 0) {
            return -1;
        }

        int y = 0;
        for (int i = 0; i < getNumSlots(); i++) {
            int h = getSlotHeight(i);
            if (my >= y && my < y + h) {
                return i;
            }
            y += h;
        }
        return -1;
    }

    public int getClickedSlot(int my) {
        return getSlot(my - windowBounds().y + scrolledPixels());
    }

    @Override
    public int scrolledPixels() {
        int scrolled = super.scrolledPixels();
        if (!smoothScroll) {
            int slot = getSlot(scrolled);
            int sloty = getSlotY(slot);
            int sloth = getSlotHeight(slot);
            scrolled = sloty + (int) ((scrolled - sloty) / (double) sloth + 0.5) * sloth;
        }
        return scrolled;
    }

    /**
     * @return -1 for left, 1 for right
     */
    public int scrollbarAlignment() {
        return 1;
    }

    @Override
    public int scrollbarGuideAlignment() {
        return scrollbarAlignment();
    }

    @Override
    public Rectangle scrollbarBounds() {
        Rectangle r = super.scrollbarBounds();
        if (scrollbarAlignment() == -1) {
            r.x = x;
        }
        return r;
    }

    public void showSlot(int slot) {
        showSlot(getSlotY(slot), getSlotHeight(slot));
    }

    @Override
    public void slotDown(int mx, int my, int button) {
        int slot = getSlot(my);
        click.mouseDown(slot >= 0 ? slot : null, button);
    }

    @Override
    public void slotUp(int mx, int my, int button) {
        int slot = getSlot(my);
        int c = click.mouseUp(slot >= 0 ? slot : null, button);
        if (c > 0 && slot >= 0) {
            slotClicked(slot, button, mx, my - getSlotY(slot), c);
        }
    }

    @Override
    public void keyTyped(char c, int keycode) {
        if (!focused) {
            return;
        }

        if (keycode == Keyboard.KEY_UP) {
            selectPrev();
        }
        if (keycode == Keyboard.KEY_DOWN) {
            selectNext();
        }
        if (keycode == Keyboard.KEY_RETURN && actionCommand != null) {
            sendAction(actionCommand);
        }
    }

    @Override
    public void drawContent(int mx, int my, float frame) {
        int scrolled = scrolledPixels();
        Rectangle w = windowBounds();
        int y = 0;
        for (int slot = 0; slot < getNumSlots(); slot++) {
            int h = getSlotHeight(slot);
            if (y + h > scrolled && y < scrolled + w.height) {
                drawSlot(slot, w.x, w.y + y - scrolledPixels(), mx, my - y, frame);
            }
            y += h;
        }
    }
}